diff --git a/sentry_sdk/integrations/aws_lambda.py b/sentry_sdk/integrations/aws_lambda.py
index cd2b3cc417..8899cc53b2 100644
--- a/sentry_sdk/integrations/aws_lambda.py
+++ b/sentry_sdk/integrations/aws_lambda.py
@@ -160,7 +160,7 @@ def sentry_handler(aws_event, aws_context, *args, **kwargs):
                 headers = {}
 
             with sentry_sdk.continue_trace(headers):
-                with sentry_sdk.start_transaction(
+                with sentry_sdk.start_span(
                     op=OP.FUNCTION_AWS,
                     name=aws_context.function_name,
                     source=TRANSACTION_SOURCE_COMPONENT,
diff --git a/sentry_sdk/integrations/celery/__init__.py b/sentry_sdk/integrations/celery/__init__.py
index a943871335..43321ec89b 100644
--- a/sentry_sdk/integrations/celery/__init__.py
+++ b/sentry_sdk/integrations/celery/__init__.py
@@ -313,7 +313,7 @@ def _inner(*args, **kwargs):
             # something such as attribute access can fail.
             headers = args[3].get("headers") or {}
             with sentry_sdk.continue_trace(headers):
-                with sentry_sdk.start_transaction(
+                with sentry_sdk.start_span(
                     op=OP.QUEUE_TASK_CELERY,
                     name=task.name,
                     source=TRANSACTION_SOURCE_TASK,
diff --git a/sentry_sdk/integrations/gcp.py b/sentry_sdk/integrations/gcp.py
index dd23ad1e0a..ec626ed699 100644
--- a/sentry_sdk/integrations/gcp.py
+++ b/sentry_sdk/integrations/gcp.py
@@ -87,7 +87,7 @@ def sentry_func(functionhandler, gcp_event, *args, **kwargs):
                 headers = gcp_event.headers
 
             with sentry_sdk.continue_trace(headers):
-                with sentry_sdk.start_transaction(
+                with sentry_sdk.start_span(
                     op=OP.FUNCTION_GCP,
                     name=environ.get("FUNCTION_NAME", ""),
                     source=TRANSACTION_SOURCE_COMPONENT,
diff --git a/sentry_sdk/integrations/grpc/aio/server.py b/sentry_sdk/integrations/grpc/aio/server.py
index 6d38e91363..4d54b0605c 100644
--- a/sentry_sdk/integrations/grpc/aio/server.py
+++ b/sentry_sdk/integrations/grpc/aio/server.py
@@ -45,7 +45,7 @@ async def wrapped(request, context):
 
                 # What if the headers are empty?
                 with sentry_sdk.continue_trace(dict(context.invocation_metadata())):
-                    with sentry_sdk.start_transaction(
+                    with sentry_sdk.start_span(
                         op=OP.GRPC_SERVER,
                         name=name,
                         source=TRANSACTION_SOURCE_CUSTOM,
diff --git a/sentry_sdk/integrations/grpc/server.py b/sentry_sdk/integrations/grpc/server.py
index fb123c5ca4..d12b43b92b 100644
--- a/sentry_sdk/integrations/grpc/server.py
+++ b/sentry_sdk/integrations/grpc/server.py
@@ -39,7 +39,7 @@ def behavior(request, context):
                     metadata = dict(context.invocation_metadata())
 
                     with sentry_sdk.continue_trace(metadata):
-                        with sentry_sdk.start_transaction(
+                        with sentry_sdk.start_span(
                             op=OP.GRPC_SERVER,
                             name=name,
                             source=TRANSACTION_SOURCE_CUSTOM,
diff --git a/sentry_sdk/integrations/tornado.py b/sentry_sdk/integrations/tornado.py
index bb40fbf625..1af8950aa4 100644
--- a/sentry_sdk/integrations/tornado.py
+++ b/sentry_sdk/integrations/tornado.py
@@ -125,7 +125,7 @@ def _handle_request_impl(self):
         scope.add_event_processor(processor)
 
         with sentry_sdk.continue_trace(headers):
-            with sentry_sdk.start_transaction(
+            with sentry_sdk.start_span(
                 op=OP.HTTP_SERVER,
                 # Like with all other integrations, this is our
                 # fallback transaction in case there is no route.
diff --git a/sentry_sdk/utils.py b/sentry_sdk/utils.py
index 16dfd9c4fa..403ac84220 100644
--- a/sentry_sdk/utils.py
+++ b/sentry_sdk/utils.py
@@ -1802,7 +1802,7 @@ def ensure_integration_enabled(
     ```python
     @ensure_integration_enabled(MyIntegration, my_function)
     def patch_my_function():
-        with sentry_sdk.start_transaction(...):
+        with sentry_sdk.start_span(...):
             return my_function()
     ```
     """
diff --git a/tests/integrations/aiohttp/test_aiohttp.py b/tests/integrations/aiohttp/test_aiohttp.py
index 4b491b152e..7960bc2dcc 100644
--- a/tests/integrations/aiohttp/test_aiohttp.py
+++ b/tests/integrations/aiohttp/test_aiohttp.py
@@ -15,7 +15,7 @@
     HTTPUnavailableForLegalReasons,
 )
 
-from sentry_sdk import capture_message, start_transaction
+from sentry_sdk import capture_message, start_span
 from sentry_sdk.integrations.aiohttp import AioHttpIntegration
 from tests.conftest import ApproxDict
 
@@ -417,7 +417,7 @@ async def hello(request):
     # The aiohttp_client is instrumented so will generate the sentry-trace header and add request.
     # Get the sentry-trace header from the request so we can later compare with transaction events.
     client = await aiohttp_client(app)
-    with start_transaction():
+    with start_span(name="request"):
         # Headers are only added to the span if there is an active transaction
         resp = await client.get("/")
 
@@ -496,7 +496,7 @@ async def handler(request):
 
     raw_server = await aiohttp_raw_server(handler)
 
-    with start_transaction():
+    with start_span(name="breadcrumb"):
         events = capture_events()
 
         client = await aiohttp_client(raw_server)
@@ -538,7 +538,7 @@ async def handler(request):
 
     raw_server = await aiohttp_raw_server(handler)
 
-    with start_transaction(
+    with start_span(
         name="/interactions/other-dogs/new-dog",
         op="greeting.sniff",
     ) as transaction:
@@ -573,7 +573,7 @@ async def handler(request):
 
     raw_server = await aiohttp_raw_server(handler)
 
-    with start_transaction(
+    with start_span(
         name="/interactions/other-dogs/new-dog",
         op="greeting.sniff",
     ) as transaction:
diff --git a/tests/integrations/anthropic/test_anthropic.py b/tests/integrations/anthropic/test_anthropic.py
index 4a7d7ed458..ece2cfe7a3 100644
--- a/tests/integrations/anthropic/test_anthropic.py
+++ b/tests/integrations/anthropic/test_anthropic.py
@@ -42,7 +42,7 @@ async def __call__(self, *args, **kwargs):
 except ImportError:
     from anthropic.types.content_block import ContentBlock as TextBlock
 
-from sentry_sdk import start_transaction
+from sentry_sdk import start_span
 from sentry_sdk.consts import OP, SPANDATA
 from sentry_sdk.integrations.anthropic import AnthropicIntegration
 
@@ -90,7 +90,7 @@ def test_nonstreaming_create_message(
         }
     ]
 
-    with start_transaction(name="anthropic"):
+    with start_span(name="anthropic"):
         response = client.messages.create(
             max_tokens=1024, messages=messages, model="model"
         )
@@ -160,7 +160,7 @@ async def test_nonstreaming_create_message_async(
         }
     ]
 
-    with start_transaction(name="anthropic"):
+    with start_span(name="anthropic"):
         response = await client.messages.create(
             max_tokens=1024, messages=messages, model="model"
         )
@@ -263,7 +263,7 @@ def test_streaming_create_message(
         }
     ]
 
-    with start_transaction(name="anthropic"):
+    with start_span(name="anthropic"):
         message = client.messages.create(
             max_tokens=1024, messages=messages, model="model", stream=True
         )
@@ -368,7 +368,7 @@ async def test_streaming_create_message_async(
         }
     ]
 
-    with start_transaction(name="anthropic"):
+    with start_span(name="anthropic"):
         message = await client.messages.create(
             max_tokens=1024, messages=messages, model="model", stream=True
         )
@@ -500,7 +500,7 @@ def test_streaming_create_message_with_input_json_delta(
         }
     ]
 
-    with start_transaction(name="anthropic"):
+    with start_span(name="anthropic"):
         message = client.messages.create(
             max_tokens=1024, messages=messages, model="model", stream=True
         )
@@ -639,7 +639,7 @@ async def test_streaming_create_message_with_input_json_delta_async(
         }
     ]
 
-    with start_transaction(name="anthropic"):
+    with start_span(name="anthropic"):
         message = await client.messages.create(
             max_tokens=1024, messages=messages, model="model", stream=True
         )
@@ -736,7 +736,7 @@ def test_span_origin(sentry_init, capture_events):
         }
     ]
 
-    with start_transaction(name="anthropic"):
+    with start_span(name="anthropic"):
         client.messages.create(max_tokens=1024, messages=messages, model="model")
 
     (event,) = events
@@ -763,7 +763,7 @@ async def test_span_origin_async(sentry_init, capture_events):
         }
     ]
 
-    with start_transaction(name="anthropic"):
+    with start_span(name="anthropic"):
         await client.messages.create(max_tokens=1024, messages=messages, model="model")
 
     (event,) = events
diff --git a/tests/integrations/arq/test_arq.py b/tests/integrations/arq/test_arq.py
index e74395e26c..0ebb97cd2b 100644
--- a/tests/integrations/arq/test_arq.py
+++ b/tests/integrations/arq/test_arq.py
@@ -1,7 +1,7 @@
 import asyncio
 import pytest
 
-from sentry_sdk import get_client, start_transaction
+from sentry_sdk import get_client, start_span
 from sentry_sdk.integrations.arq import ArqIntegration
 
 import arq.worker
@@ -292,7 +292,7 @@ async def dummy_job(_):
 
     events = capture_events()
 
-    with start_transaction() as transaction:
+    with start_span(name="test") as transaction:
         await pool.enqueue_job("dummy_job")
 
     (event,) = events
@@ -343,7 +343,7 @@ async def dummy_job(_):
 
     events = capture_events()
 
-    with start_transaction():
+    with start_span(name="job"):
         await pool.enqueue_job("dummy_job")
 
     (event,) = events
diff --git a/tests/integrations/celery/test_celery.py b/tests/integrations/celery/test_celery.py
index 1011429098..2f8de6968a 100644
--- a/tests/integrations/celery/test_celery.py
+++ b/tests/integrations/celery/test_celery.py
@@ -7,7 +7,7 @@
 from celery.bin import worker
 
 import sentry_sdk
-from sentry_sdk import start_transaction, get_current_span
+from sentry_sdk import start_span, get_current_span
 from sentry_sdk.integrations.celery import (
     CeleryIntegration,
     _wrap_task_run,
@@ -126,7 +126,7 @@ def dummy_task(x, y):
         foo = 42  # noqa
         return x / y
 
-    with start_transaction(op="unit test transaction") as transaction:
+    with start_span(op="unit test transaction") as transaction:
         celery_invocation(dummy_task, 1, 2)
         _, expected_context = celery_invocation(dummy_task, 1, 0)
 
@@ -195,7 +195,7 @@ def dummy_task(x, y):
 
     events = capture_events()
 
-    with start_transaction(name="submission") as transaction:
+    with start_span(name="submission") as transaction:
         celery_invocation(dummy_task, 1, 0 if task_fails else 1)
 
     if task_fails:
@@ -275,11 +275,11 @@ def test_simple_no_propagation(capture_events, init_celery):
     def dummy_task():
         1 / 0
 
-    with start_transaction() as transaction:
+    with start_span(name="task") as root_span:
         dummy_task.delay()
 
     (event,) = events
-    assert event["contexts"]["trace"]["trace_id"] != transaction.trace_id
+    assert event["contexts"]["trace"]["trace_id"] != root_span.trace_id
     assert event["transaction"] == "dummy_task"
     (exception,) = event["exception"]["values"]
     assert exception["type"] == "ZeroDivisionError"
@@ -350,7 +350,7 @@ def dummy_task(self):
         runs.append(1)
         1 / 0
 
-    with start_transaction(name="submit_celery"):
+    with start_span(name="submit_celery"):
         # Curious: Cannot use delay() here or py2.7-celery-4.2 crashes
         res = dummy_task.apply_async()
 
@@ -469,7 +469,7 @@ def __call__(self, *args, **kwargs):
     def dummy_task(x, y):
         return x / y
 
-    with start_transaction():
+    with start_span(name="celery"):
         celery_invocation(dummy_task, 1, 0)
 
     assert not events
@@ -510,7 +510,7 @@ def test_baggage_propagation(init_celery):
     def dummy_task(self, x, y):
         return _get_headers(self)
 
-    with start_transaction() as transaction:
+    with start_span(name="task") as root_span:
         result = dummy_task.apply_async(
             args=(1, 0),
             headers={"baggage": "custom=value"},
@@ -519,7 +519,7 @@ def dummy_task(self, x, y):
         assert sorted(result["baggage"].split(",")) == sorted(
             [
                 "sentry-release=abcdef",
-                "sentry-trace_id={}".format(transaction.trace_id),
+                "sentry-trace_id={}".format(root_span.trace_id),
                 "sentry-environment=production",
                 "sentry-sample_rate=1.0",
                 "sentry-sampled=true",
@@ -542,8 +542,8 @@ def dummy_task(self, message):
         trace_id = get_current_span().trace_id
         return trace_id
 
-    with start_transaction() as transaction:
-        transaction_trace_id = transaction.trace_id
+    with start_span(name="task") as root_span:
+        transaction_trace_id = root_span.trace_id
 
         # should propagate trace
         task_transaction_id = dummy_task.apply_async(
@@ -710,7 +710,7 @@ def publish(*args, **kwargs):
     @celery.task()
     def task(): ...
 
-    with start_transaction():
+    with start_span(name="task"):
         task.apply_async()
 
     (event,) = events
@@ -773,7 +773,7 @@ def publish(*args, **kwargs):
     @celery.task()
     def task(): ...
 
-    with start_transaction(name="custom_transaction"):
+    with start_span(name="custom_transaction"):
         task.apply_async()
 
     (event,) = events
@@ -799,7 +799,7 @@ def test_send_task_wrapped(
 
     events = capture_events()
 
-    with sentry_sdk.start_transaction(name="custom_transaction"):
+    with sentry_sdk.start_span(name="custom_transaction"):
         celery.send_task("very_creative_task_name", args=(1, 2), kwargs={"foo": "bar"})
 
     (call,) = patched_send_task.call_args_list  # We should have exactly one call
diff --git a/tests/integrations/celery/test_update_celery_task_headers.py b/tests/integrations/celery/test_update_celery_task_headers.py
index 705c00de58..709e49b54a 100644
--- a/tests/integrations/celery/test_update_celery_task_headers.py
+++ b/tests/integrations/celery/test_update_celery_task_headers.py
@@ -75,7 +75,7 @@ def test_span_with_transaction(sentry_init):
     headers = {}
     monitor_beat_tasks = False
 
-    with sentry_sdk.start_transaction(name="test_transaction") as transaction:
+    with sentry_sdk.start_span(name="test_transaction") as transaction:
         with sentry_sdk.start_span(op="test_span") as span:
             outgoing_headers = _update_celery_task_headers(
                 headers, span, monitor_beat_tasks
@@ -97,7 +97,7 @@ def test_span_with_transaction_custom_headers(sentry_init):
         "sentry-trace": SENTRY_TRACE_VALUE,
     }
 
-    with sentry_sdk.start_transaction(name="test_transaction") as transaction:
+    with sentry_sdk.start_span(name="test_transaction") as transaction:
         with sentry_sdk.start_span(op="test_span") as span:
             outgoing_headers = _update_celery_task_headers(headers, span, False)
 
diff --git a/tests/integrations/clickhouse_driver/test_clickhouse_driver.py b/tests/integrations/clickhouse_driver/test_clickhouse_driver.py
index 2c3d3c41a4..7eb0462231 100644
--- a/tests/integrations/clickhouse_driver/test_clickhouse_driver.py
+++ b/tests/integrations/clickhouse_driver/test_clickhouse_driver.py
@@ -8,7 +8,7 @@
 import clickhouse_driver
 from clickhouse_driver import Client, connect
 
-from sentry_sdk import start_transaction, capture_message
+from sentry_sdk import start_span, capture_message
 from sentry_sdk.integrations.clickhouse_driver import ClickhouseDriverIntegration
 from tests.conftest import ApproxDict
 
@@ -227,7 +227,7 @@ def test_clickhouse_client_spans(
     transaction_trace_id = None
     transaction_span_id = None
 
-    with start_transaction(name="test_clickhouse_transaction") as transaction:
+    with start_span(name="test_clickhouse_transaction") as transaction:
         transaction_trace_id = transaction.trace_id
         transaction_span_id = transaction.span_id
 
@@ -360,7 +360,7 @@ def test_clickhouse_client_spans_with_pii(sentry_init, capture_events) -> None:
     transaction_trace_id = None
     transaction_span_id = None
 
-    with start_transaction(name="test_clickhouse_transaction") as transaction:
+    with start_span(name="test_clickhouse_transaction") as transaction:
         transaction_trace_id = transaction.trace_id
         transaction_span_id = transaction.span_id
 
@@ -701,7 +701,7 @@ def test_clickhouse_dbapi_spans(sentry_init, capture_events, capture_envelopes)
     transaction_trace_id = None
     transaction_span_id = None
 
-    with start_transaction(name="test_clickhouse_transaction") as transaction:
+    with start_span(name="test_clickhouse_transaction") as transaction:
         transaction_trace_id = transaction.trace_id
         transaction_span_id = transaction.span_id
 
@@ -835,7 +835,7 @@ def test_clickhouse_dbapi_spans_with_pii(
     transaction_trace_id = None
     transaction_span_id = None
 
-    with start_transaction(name="test_clickhouse_transaction") as transaction:
+    with start_span(name="test_clickhouse_transaction") as transaction:
         transaction_trace_id = transaction.trace_id
         transaction_span_id = transaction.span_id
 
@@ -975,7 +975,7 @@ def test_span_origin(sentry_init, capture_events, capture_envelopes) -> None:
 
     events = capture_events()
 
-    with start_transaction(name="test_clickhouse_transaction"):
+    with start_span(name="test_clickhouse_transaction"):
         conn = connect("clickhouse://localhost")
         cursor = conn.cursor()
         cursor.execute("SELECT 1")
diff --git a/tests/integrations/cohere/test_cohere.py b/tests/integrations/cohere/test_cohere.py
index 672d71b6b3..ff41ceba11 100644
--- a/tests/integrations/cohere/test_cohere.py
+++ b/tests/integrations/cohere/test_cohere.py
@@ -4,7 +4,7 @@
 import pytest
 from cohere import Client, ChatMessage
 
-from sentry_sdk import start_transaction
+from sentry_sdk import start_span
 from sentry_sdk.integrations.cohere import CohereIntegration
 
 from unittest import mock  # python 3.3 and above
@@ -41,7 +41,7 @@ def test_nonstreaming_chat(
         )
     )
 
-    with start_transaction(name="cohere tx"):
+    with start_span(name="cohere tx"):
         response = client.chat(
             model="some-model",
             chat_history=[ChatMessage(role="SYSTEM", message="some context")],
@@ -110,7 +110,7 @@ def test_streaming_chat(sentry_init, capture_events, send_default_pii, include_p
         )
     )
 
-    with start_transaction(name="cohere tx"):
+    with start_span(name="cohere tx"):
         responses = list(
             client.chat_stream(
                 model="some-model",
@@ -186,7 +186,7 @@ def test_embed(sentry_init, capture_events, send_default_pii, include_prompts):
         )
     )
 
-    with start_transaction(name="cohere tx"):
+    with start_span(name="cohere tx"):
         response = client.embed(texts=["hello"], model="text-embedding-3-large")
 
     assert len(response.embeddings[0]) == 3
@@ -227,7 +227,7 @@ def test_span_origin_chat(sentry_init, capture_events):
         )
     )
 
-    with start_transaction(name="cohere tx"):
+    with start_span(name="cohere tx"):
         client.chat(
             model="some-model",
             chat_history=[ChatMessage(role="SYSTEM", message="some context")],
@@ -265,7 +265,7 @@ def test_span_origin_embed(sentry_init, capture_events):
         )
     )
 
-    with start_transaction(name="cohere tx"):
+    with start_span(name="cohere tx"):
         client.embed(texts=["hello"], model="text-embedding-3-large")
 
     (event,) = events
diff --git a/tests/integrations/django/test_cache_module.py b/tests/integrations/django/test_cache_module.py
index 03e4925ab0..2d8cc3d5d6 100644
--- a/tests/integrations/django/test_cache_module.py
+++ b/tests/integrations/django/test_cache_module.py
@@ -530,7 +530,7 @@ def test_cache_spans_get_many(
 
     from django.core.cache import cache
 
-    with sentry_sdk.start_transaction(name="caches"):
+    with sentry_sdk.start_span(name="caches"):
         cache.get_many([f"S{id}", f"S{id+1}"])
         cache.set(f"S{id}", "Sensitive1")
         cache.get_many([f"S{id}", f"S{id+1}"])
@@ -574,7 +574,7 @@ def test_cache_spans_set_many(
 
     from django.core.cache import cache
 
-    with sentry_sdk.start_transaction(name="caches"):
+    with sentry_sdk.start_span(name="caches"):
         cache.set_many({f"S{id}": "Sensitive1", f"S{id+1}": "Sensitive2"})
         cache.get(f"S{id}")
 
diff --git a/tests/integrations/django/test_db_query_data.py b/tests/integrations/django/test_db_query_data.py
index ccbe6ee28a..82f1f339a6 100644
--- a/tests/integrations/django/test_db_query_data.py
+++ b/tests/integrations/django/test_db_query_data.py
@@ -16,7 +16,7 @@
 from freezegun import freeze_time
 from werkzeug.test import Client
 
-from sentry_sdk import start_transaction, start_span
+from sentry_sdk import start_span
 from sentry_sdk.consts import SPANDATA
 from sentry_sdk.integrations.django import DjangoIntegration
 from sentry_sdk.tracing_utils import record_sql_queries
@@ -496,7 +496,7 @@ def test_db_span_origin_executemany(sentry_init, client, capture_events):
     if "postgres" not in connections:
         pytest.skip("postgres tests disabled")
 
-    with start_transaction(name="test_transaction"):
+    with start_span(name="test_transaction"):
         from django.db import connection, transaction
 
         cursor = connection.cursor()
diff --git a/tests/integrations/huggingface_hub/test_huggingface_hub.py b/tests/integrations/huggingface_hub/test_huggingface_hub.py
index f43159d80e..7e84d648ee 100644
--- a/tests/integrations/huggingface_hub/test_huggingface_hub.py
+++ b/tests/integrations/huggingface_hub/test_huggingface_hub.py
@@ -6,7 +6,7 @@
 )
 from huggingface_hub.errors import OverloadedError
 
-from sentry_sdk import start_transaction
+from sentry_sdk import start_span
 from sentry_sdk.integrations.huggingface_hub import HuggingfaceHubIntegration
 
 from unittest import mock  # python 3.3 and above
@@ -43,7 +43,7 @@ def test_nonstreaming_chat_completion(
         client.post = mock.Mock(
             return_value=b'[{"generated_text": "the model response"}]'
         )
-    with start_transaction(name="huggingface_hub tx"):
+    with start_span(name="huggingface_hub tx"):
         response = client.text_generation(
             prompt="hello",
             details=details_arg,
@@ -95,7 +95,7 @@ def test_streaming_chat_completion(
             }""",
         ]
     )
-    with start_transaction(name="huggingface_hub tx"):
+    with start_span(name="huggingface_hub tx"):
         response = list(
             client.text_generation(
                 prompt="hello",
@@ -154,7 +154,7 @@ def test_span_origin(sentry_init, capture_events):
             }""",
         ]
     )
-    with start_transaction(name="huggingface_hub tx"):
+    with start_span(name="huggingface_hub tx"):
         list(
             client.text_generation(
                 prompt="hello",
diff --git a/tests/integrations/langchain/test_langchain.py b/tests/integrations/langchain/test_langchain.py
index b9e5705b88..2ac6679321 100644
--- a/tests/integrations/langchain/test_langchain.py
+++ b/tests/integrations/langchain/test_langchain.py
@@ -14,7 +14,7 @@
 from langchain_core.messages import BaseMessage, AIMessageChunk
 from langchain_core.outputs import ChatGenerationChunk
 
-from sentry_sdk import start_transaction
+from sentry_sdk import start_span
 from sentry_sdk.integrations.langchain import LangchainIntegration
 from langchain.agents import tool, AgentExecutor, create_openai_tools_agent
 from langchain_core.prompts import ChatPromptTemplate, MessagesPlaceholder
@@ -163,7 +163,7 @@ def test_langchain_agent(
 
     agent_executor = AgentExecutor(agent=agent, tools=[get_word_length], verbose=True)
 
-    with start_transaction():
+    with start_span(name="agent"):
         list(agent_executor.stream({"input": "How many letters in the word eudca"}))
 
     tx = events[0]
@@ -237,7 +237,7 @@ def test_langchain_error(sentry_init, capture_events):
 
     agent_executor = AgentExecutor(agent=agent, tools=[get_word_length], verbose=True)
 
-    with start_transaction(), pytest.raises(Exception):
+    with start_span(name="agent"), pytest.raises(Exception):
         list(agent_executor.stream({"input": "How many letters in the word eudca"}))
 
     error = events[0]
@@ -332,7 +332,7 @@ def test_span_origin(sentry_init, capture_events):
 
     agent_executor = AgentExecutor(agent=agent, tools=[get_word_length], verbose=True)
 
-    with start_transaction():
+    with start_span(name="agent"):
         list(agent_executor.stream({"input": "How many letters in the word eudca"}))
 
     (event,) = events
diff --git a/tests/integrations/openai/test_openai.py b/tests/integrations/openai/test_openai.py
index 011192e49f..793cda8b31 100644
--- a/tests/integrations/openai/test_openai.py
+++ b/tests/integrations/openai/test_openai.py
@@ -6,7 +6,7 @@
 from openai.types.chat.chat_completion_chunk import ChoiceDelta, Choice as DeltaChoice
 from openai.types.create_embedding_response import Usage as EmbeddingTokenUsage
 
-from sentry_sdk import start_transaction
+from sentry_sdk import start_span
 from sentry_sdk.integrations.openai import (
     OpenAIIntegration,
     _calculate_chat_completion_usage,
@@ -67,7 +67,7 @@ def test_nonstreaming_chat_completion(
     client = OpenAI(api_key="z")
     client.chat.completions._post = mock.Mock(return_value=EXAMPLE_CHAT_COMPLETION)
 
-    with start_transaction(name="openai tx"):
+    with start_span(name="openai tx"):
         response = (
             client.chat.completions.create(
                 model="some-model", messages=[{"role": "system", "content": "hello"}]
@@ -112,7 +112,7 @@ async def test_nonstreaming_chat_completion_async(
     client = AsyncOpenAI(api_key="z")
     client.chat.completions._post = AsyncMock(return_value=EXAMPLE_CHAT_COMPLETION)
 
-    with start_transaction(name="openai tx"):
+    with start_span(name="openai tx"):
         response = await client.chat.completions.create(
             model="some-model", messages=[{"role": "system", "content": "hello"}]
         )
@@ -204,7 +204,7 @@ def test_streaming_chat_completion(
     ]
 
     client.chat.completions._post = mock.Mock(return_value=returned_stream)
-    with start_transaction(name="openai tx"):
+    with start_span(name="openai tx"):
         response_stream = client.chat.completions.create(
             model="some-model", messages=[{"role": "system", "content": "hello"}]
         )
@@ -298,7 +298,7 @@ async def test_streaming_chat_completion_async(
     )
 
     client.chat.completions._post = AsyncMock(return_value=returned_stream)
-    with start_transaction(name="openai tx"):
+    with start_span(name="openai tx"):
         response_stream = await client.chat.completions.create(
             model="some-model", messages=[{"role": "system", "content": "hello"}]
         )
@@ -392,7 +392,7 @@ def test_embeddings_create(
     )
 
     client.embeddings._post = mock.Mock(return_value=returned_embedding)
-    with start_transaction(name="openai tx"):
+    with start_span(name="openai tx"):
         response = client.embeddings.create(
             input="hello", model="text-embedding-3-large"
         )
@@ -440,7 +440,7 @@ async def test_embeddings_create_async(
     )
 
     client.embeddings._post = AsyncMock(return_value=returned_embedding)
-    with start_transaction(name="openai tx"):
+    with start_span(name="openai tx"):
         response = await client.embeddings.create(
             input="hello", model="text-embedding-3-large"
         )
@@ -525,7 +525,7 @@ def test_span_origin_nonstreaming_chat(sentry_init, capture_events):
     client = OpenAI(api_key="z")
     client.chat.completions._post = mock.Mock(return_value=EXAMPLE_CHAT_COMPLETION)
 
-    with start_transaction(name="openai tx"):
+    with start_span(name="openai tx"):
         client.chat.completions.create(
             model="some-model", messages=[{"role": "system", "content": "hello"}]
         )
@@ -547,7 +547,7 @@ async def test_span_origin_nonstreaming_chat_async(sentry_init, capture_events):
     client = AsyncOpenAI(api_key="z")
     client.chat.completions._post = AsyncMock(return_value=EXAMPLE_CHAT_COMPLETION)
 
-    with start_transaction(name="openai tx"):
+    with start_span(name="openai tx"):
         await client.chat.completions.create(
             model="some-model", messages=[{"role": "system", "content": "hello"}]
         )
@@ -604,7 +604,7 @@ def test_span_origin_streaming_chat(sentry_init, capture_events):
     ]
 
     client.chat.completions._post = mock.Mock(return_value=returned_stream)
-    with start_transaction(name="openai tx"):
+    with start_span(name="openai tx"):
         response_stream = client.chat.completions.create(
             model="some-model", messages=[{"role": "system", "content": "hello"}]
         )
@@ -668,7 +668,7 @@ async def test_span_origin_streaming_chat_async(sentry_init, capture_events):
     )
 
     client.chat.completions._post = AsyncMock(return_value=returned_stream)
-    with start_transaction(name="openai tx"):
+    with start_span(name="openai tx"):
         response_stream = await client.chat.completions.create(
             model="some-model", messages=[{"role": "system", "content": "hello"}]
         )
@@ -703,7 +703,7 @@ def test_span_origin_embeddings(sentry_init, capture_events):
     )
 
     client.embeddings._post = mock.Mock(return_value=returned_embedding)
-    with start_transaction(name="openai tx"):
+    with start_span(name="openai tx"):
         client.embeddings.create(input="hello", model="text-embedding-3-large")
 
     (event,) = events
@@ -733,7 +733,7 @@ async def test_span_origin_embeddings_async(sentry_init, capture_events):
     )
 
     client.embeddings._post = AsyncMock(return_value=returned_embedding)
-    with start_transaction(name="openai tx"):
+    with start_span(name="openai tx"):
         await client.embeddings.create(input="hello", model="text-embedding-3-large")
 
     (event,) = events
diff --git a/tests/integrations/redis/test_redis_cache_module.py b/tests/integrations/redis/test_redis_cache_module.py
index e02b1ec31a..b1c012e5ee 100644
--- a/tests/integrations/redis/test_redis_cache_module.py
+++ b/tests/integrations/redis/test_redis_cache_module.py
@@ -24,7 +24,7 @@ def test_no_cache_basic(sentry_init, capture_events, render_span_tree):
     events = capture_events()
 
     connection = FakeStrictRedis()
-    with sentry_sdk.start_transaction():
+    with sentry_sdk.start_span(name="cache"):
         connection.get("mycachekey")
 
     (event,) = events
@@ -49,7 +49,7 @@ def test_cache_basic(sentry_init, capture_events, render_span_tree):
     events = capture_events()
 
     connection = FakeStrictRedis()
-    with sentry_sdk.start_transaction():
+    with sentry_sdk.start_span(name="cache"):
         connection.hget("mycachekey", "myfield")
         connection.get("mycachekey")
         connection.set("mycachekey1", "bla")
@@ -87,7 +87,7 @@ def test_cache_keys(sentry_init, capture_events, render_span_tree):
     events = capture_events()
 
     connection = FakeStrictRedis()
-    with sentry_sdk.start_transaction():
+    with sentry_sdk.start_span(name="cache"):
         connection.get("somethingelse")
         connection.get("blub")
         connection.get("blubkeything")
@@ -120,7 +120,7 @@ def test_cache_data(sentry_init, capture_events):
     events = capture_events()
 
     connection = FakeStrictRedis(host="mycacheserver.io", port=6378)
-    with sentry_sdk.start_transaction():
+    with sentry_sdk.start_span(name="cache"):
         connection.get("mycachekey")
         connection.set("mycachekey", "事实胜于雄辩")
         connection.get("mycachekey")
@@ -203,7 +203,7 @@ def test_cache_prefixes(sentry_init, capture_events):
     events = capture_events()
 
     connection = FakeStrictRedis()
-    with sentry_sdk.start_transaction():
+    with sentry_sdk.start_span(name="cache"):
         connection.mget("yes", "no")
         connection.mget("no", 1, "yes")
         connection.mget("no", "yes.1", "yes.2")
diff --git a/tests/integrations/redis_py_cluster_legacy/test_redis_py_cluster_legacy.py b/tests/integrations/redis_py_cluster_legacy/test_redis_py_cluster_legacy.py
index 5e0b724436..a530fec115 100644
--- a/tests/integrations/redis_py_cluster_legacy/test_redis_py_cluster_legacy.py
+++ b/tests/integrations/redis_py_cluster_legacy/test_redis_py_cluster_legacy.py
@@ -4,7 +4,7 @@
 import rediscluster
 
 from sentry_sdk import capture_message
-from sentry_sdk.api import start_transaction
+from sentry_sdk.api import start_span
 from sentry_sdk.consts import SPANDATA
 from sentry_sdk.integrations.redis import RedisIntegration
 from tests.conftest import ApproxDict
@@ -84,7 +84,7 @@ def test_rediscluster_pipeline(
     events = capture_events()
 
     rc = rediscluster.RedisCluster(connection_pool=MOCK_CONNECTION_POOL)
-    with start_transaction():
+    with start_span(name="redis"):
         pipeline = rc.pipeline()
         pipeline.get("foo")
         pipeline.set("bar", 1)
@@ -120,7 +120,7 @@ def test_db_connection_attributes_client(sentry_init, capture_events, redisclust
     events = capture_events()
 
     rc = rediscluster_cls(connection_pool=MOCK_CONNECTION_POOL)
-    with start_transaction():
+    with start_span(name="redis"):
         rc.get("foobar")
 
     (event,) = events
@@ -147,7 +147,7 @@ def test_db_connection_attributes_pipeline(
     events = capture_events()
 
     rc = rediscluster.RedisCluster(connection_pool=MOCK_CONNECTION_POOL)
-    with start_transaction():
+    with start_span(name="redis"):
         pipeline = rc.pipeline()
         pipeline.get("foo")
         pipeline.execute()
diff --git a/tests/integrations/socket/test_socket.py b/tests/integrations/socket/test_socket.py
index e629114b2b..500e9b5608 100644
--- a/tests/integrations/socket/test_socket.py
+++ b/tests/integrations/socket/test_socket.py
@@ -1,6 +1,6 @@
 import socket
 
-from sentry_sdk import start_transaction
+from sentry_sdk import start_span
 from sentry_sdk.integrations.socket import SocketIntegration
 from tests.conftest import ApproxDict
 
@@ -9,7 +9,7 @@ def test_getaddrinfo_trace(sentry_init, capture_events):
     sentry_init(integrations=[SocketIntegration()], traces_sample_rate=1.0)
     events = capture_events()
 
-    with start_transaction():
+    with start_span(name="socket"):
         socket.getaddrinfo("example.com", 443)
 
     (event,) = events
@@ -31,7 +31,7 @@ def test_create_connection_trace(sentry_init, capture_events):
     sentry_init(integrations=[SocketIntegration()], traces_sample_rate=1.0)
     events = capture_events()
 
-    with start_transaction():
+    with start_span(name="socket"):
         socket.create_connection(("example.com", 443), timeout, None)
 
     (event,) = events
@@ -65,7 +65,7 @@ def test_span_origin(sentry_init, capture_events):
     )
     events = capture_events()
 
-    with start_transaction(name="foo"):
+    with start_span(name="foo"):
         socket.create_connection(("example.com", 443), 1, None)
 
     (event,) = events
diff --git a/tests/integrations/tornado/test_tornado.py b/tests/integrations/tornado/test_tornado.py
index 837da07434..e5dae3fcd9 100644
--- a/tests/integrations/tornado/test_tornado.py
+++ b/tests/integrations/tornado/test_tornado.py
@@ -4,7 +4,7 @@
 import pytest
 
 import sentry_sdk
-from sentry_sdk import start_transaction, capture_message
+from sentry_sdk import start_span, capture_message
 from sentry_sdk.integrations.tornado import TornadoIntegration
 
 from tornado.web import RequestHandler, Application, HTTPError
@@ -117,7 +117,7 @@ def test_transactions(tornado_testcase, sentry_init, capture_events, handler, co
     events = capture_events()
     client = tornado_testcase(Application([(r"/hi", handler)]))
 
-    with start_transaction(name="client") as span:
+    with start_span(name="client") as span:
         pass
 
     response = client.fetch(
@@ -135,7 +135,7 @@ def test_transactions(tornado_testcase, sentry_init, capture_events, handler, co
     assert client_tx["transaction"] == "client"
     assert client_tx["transaction_info"] == {
         "source": "custom"
-    }  # because this is just the start_transaction() above.
+    }  # because this is just the start_span() above.
 
     if server_error is not None:
         assert server_error["exception"]["values"][0]["type"] == "ZeroDivisionError"
diff --git a/tests/profiler/test_continuous_profiler.py b/tests/profiler/test_continuous_profiler.py
index 1b96f27036..f56afe656e 100644
--- a/tests/profiler/test_continuous_profiler.py
+++ b/tests/profiler/test_continuous_profiler.py
@@ -198,7 +198,7 @@ def test_continuous_profiler_auto_start_and_manual_stop(
 
     thread = threading.current_thread()
 
-    with sentry_sdk.start_transaction(name="profiling"):
+    with sentry_sdk.start_span(name="profiling"):
         with sentry_sdk.start_span(op="op"):
             time.sleep(0.05)
 
@@ -209,7 +209,7 @@ def test_continuous_profiler_auto_start_and_manual_stop(
 
         envelopes.clear()
 
-        with sentry_sdk.start_transaction(name="profiling"):
+        with sentry_sdk.start_span(name="profiling"):
             with sentry_sdk.start_span(op="op"):
                 time.sleep(0.05)
 
@@ -219,7 +219,7 @@ def test_continuous_profiler_auto_start_and_manual_stop(
 
         envelopes.clear()
 
-        with sentry_sdk.start_transaction(name="profiling"):
+        with sentry_sdk.start_span(name="profiling"):
             with sentry_sdk.start_span(op="op"):
                 time.sleep(0.05)
 
@@ -260,7 +260,7 @@ def test_continuous_profiler_manual_start_and_stop(
 
         envelopes.clear()
 
-        with sentry_sdk.start_transaction(name="profiling"):
+        with sentry_sdk.start_span(name="profiling"):
             with sentry_sdk.start_span(op="op"):
                 time.sleep(0.05)
 
@@ -270,7 +270,7 @@ def test_continuous_profiler_manual_start_and_stop(
 
         envelopes.clear()
 
-        with sentry_sdk.start_transaction(name="profiling"):
+        with sentry_sdk.start_span(name="profiling"):
             with sentry_sdk.start_span(op="op"):
                 time.sleep(0.05)
 
diff --git a/tests/profiler/test_transaction_profiler.py b/tests/profiler/test_transaction_profiler.py
index a77942e788..7679831be3 100644
--- a/tests/profiler/test_transaction_profiler.py
+++ b/tests/profiler/test_transaction_profiler.py
@@ -9,7 +9,7 @@
 
 import pytest
 
-from sentry_sdk import start_transaction
+from sentry_sdk import start_span
 from sentry_sdk.profiler.transaction_profiler import (
     GeventScheduler,
     Profile,
@@ -148,7 +148,7 @@ def test_profiles_sample_rate(
     with mock.patch(
         "sentry_sdk.profiler.transaction_profiler.random.random", return_value=0.5
     ):
-        with start_transaction(name="profiling"):
+        with start_span(name="profiling"):
             pass
 
     items = defaultdict(list)
@@ -219,7 +219,7 @@ def test_profiles_sampler(
     with mock.patch(
         "sentry_sdk.profiler.transaction_profiler.random.random", return_value=0.5
     ):
-        with start_transaction(name="profiling"):
+        with start_span(name="profiling"):
             pass
 
     items = defaultdict(list)
@@ -249,7 +249,7 @@ def test_minimum_unique_samples_required(
     envelopes = capture_envelopes()
     record_lost_event_calls = capture_record_lost_event_calls()
 
-    with start_transaction(name="profiling"):
+    with start_span(name="profiling"):
         pass
 
     items = defaultdict(list)
@@ -277,7 +277,7 @@ def test_profile_captured(
 
     envelopes = capture_envelopes()
 
-    with start_transaction(name="profiling"):
+    with start_span(name="profiling"):
         time.sleep(0.05)
 
     items = defaultdict(list)
diff --git a/tests/test_ai_monitoring.py b/tests/test_ai_monitoring.py
index 5e7c7432fa..9ecd75fc84 100644
--- a/tests/test_ai_monitoring.py
+++ b/tests/test_ai_monitoring.py
@@ -16,7 +16,7 @@ def tool(**kwargs):
     def pipeline():
         tool()
 
-    with sentry_sdk.start_transaction():
+    with sentry_sdk.start_span(name="pipeline"):
         pipeline()
 
     transaction = events[0]
@@ -43,7 +43,7 @@ def tool(**kwargs):
     def pipeline():
         tool()
 
-    with sentry_sdk.start_transaction():
+    with sentry_sdk.start_span(name="pipeline"):
         pipeline(sentry_tags={"user": "colin"}, sentry_data={"some_data": "value"})
 
     transaction = events[0]
@@ -74,7 +74,7 @@ async def async_tool(**kwargs):
     async def async_pipeline():
         await async_tool()
 
-    with sentry_sdk.start_transaction():
+    with sentry_sdk.start_span(name="async_pipeline"):
         await async_pipeline()
 
     transaction = events[0]
@@ -102,7 +102,7 @@ async def async_tool(**kwargs):
     async def async_pipeline():
         await async_tool()
 
-    with sentry_sdk.start_transaction():
+    with sentry_sdk.start_span(name="async_pipeline"):
         await async_pipeline(
             sentry_tags={"user": "czyber"}, sentry_data={"some_data": "value"}
         )
diff --git a/tests/test_basics.py b/tests/test_basics.py
index 3c05f9848a..cbf0177403 100644
--- a/tests/test_basics.py
+++ b/tests/test_basics.py
@@ -16,7 +16,7 @@
     capture_event,
     capture_exception,
     capture_message,
-    start_transaction,
+    start_span,
     last_event_id,
     add_breadcrumb,
     isolation_scope,
@@ -174,7 +174,7 @@ def before_send_transaction(event, hint):
         traces_sample_rate=1.0,
     )
     events = capture_events()
-    transaction = start_transaction(name="foo")
+    transaction = start_span(name="foo")
     transaction.finish()
 
     (event,) = events
@@ -191,7 +191,7 @@ def before_send_transaction_discard(event, hint):
         traces_sample_rate=1.0,
     )
     events = capture_events()
-    transaction = start_transaction(name="foo")
+    transaction = start_span(name="foo")
     transaction.finish()
 
     assert len(events) == 0
@@ -592,7 +592,7 @@ def foo(event, hint):
 
         capture_message("dropped")
 
-        with start_transaction(name="dropped"):
+        with start_span(name="dropped"):
             pass
 
         assert len(events) == 0
@@ -697,7 +697,7 @@ def test_functions_to_trace(sentry_init, capture_events):
 
     events = capture_events()
 
-    with start_transaction(name="something"):
+    with start_span(name="something"):
         time.sleep(0)
 
         for word in ["World", "You"]:
@@ -733,7 +733,7 @@ def test_functions_to_trace_with_class(sentry_init, capture_events):
 
     events = capture_events()
 
-    with start_transaction(name="something"):
+    with start_span(name="something"):
         wg = WorldGreeter("World")
         wg.greet()
         wg.greet("You")
@@ -822,7 +822,7 @@ def test_last_event_id_transaction(sentry_init):
 
     assert last_event_id() is None
 
-    with start_transaction(name="test"):
+    with start_span(name="test"):
         pass
 
     assert last_event_id() is None, "Transaction should not set last_event_id"
diff --git a/tests/test_scope.py b/tests/test_scope.py
index e7194e6caf..cdeeec72c9 100644
--- a/tests/test_scope.py
+++ b/tests/test_scope.py
@@ -785,7 +785,7 @@ def test_nested_scopes_with_tags(sentry_init, capture_envelopes):
         with sentry_sdk.new_scope() as scope2:
             scope2.set_tag("current_scope2", 1)
 
-            with sentry_sdk.start_transaction(name="trx") as trx:
+            with sentry_sdk.start_span(name="trx") as trx:
                 trx.set_tag("trx", 1)
 
                 with sentry_sdk.start_span(op="span1") as span1:
@@ -876,7 +876,7 @@ def test_last_event_id_transaction(sentry_init):
 
     assert Scope.last_event_id() is None
 
-    with sentry_sdk.start_transaction(name="test"):
+    with sentry_sdk.start_span(name="test"):
         pass
 
     assert Scope.last_event_id() is None, "Transaction should not set last_event_id"
diff --git a/tests/test_scrubber.py b/tests/test_scrubber.py
index 2c462153dd..8bef3bac10 100644
--- a/tests/test_scrubber.py
+++ b/tests/test_scrubber.py
@@ -1,7 +1,7 @@
 import sys
 import logging
 
-from sentry_sdk import capture_exception, capture_event, start_transaction, start_span
+from sentry_sdk import capture_exception, capture_event, start_span
 from sentry_sdk.utils import event_from_exception
 from sentry_sdk.scrubber import EventScrubber
 from tests.conftest import ApproxDict
@@ -145,7 +145,7 @@ def test_span_data_scrubbing(sentry_init, capture_events):
     sentry_init(traces_sample_rate=1.0)
     events = capture_events()
 
-    with start_transaction(name="hi"):
+    with start_span(name="hi"):
         with start_span(op="foo", name="bar") as span:
             span.set_data("password", "secret")
             span.set_data("datafoo", "databar")