Update README

Author: aaronj0

README.md

@@ -212,14 +212,14 @@ cd ..\
 ```
 
 #### Environment variables 
-Regardless of whether you are building CppInterOP with Cling or Clang-REPL you will need to define the following Envirnoment variables (as they clear for a new session, it is recommended that you also add these to your .bashrc in linux, .bash_profile if on MacOS, or profile.ps1 on Windows). On Linux and MacOS you define as follows
+Regardless of whether you are building CppInterOP with Cling or Clang-REPL you will need to define the following environment variables (as they clear for a new session, it is recommended that you also add these to your .bashrc in linux, .bash_profile if on MacOS, or profile.ps1 on Windows). On Linux and MacOS you define as follows
 ```
 export CB_PYTHON_DIR="$PWD/cppyy-backend/python"
 export CPPINTEROP_DIR="$CB_PYTHON_DIR/cppyy_backend"
 export CPLUS_INCLUDE_PATH="${CPLUS_INCLUDE_PATH}:${LLVM_DIR}/llvm/include:${LLVM_DIR}/clang/include:${LLVM_DIR}/build/include:${LLVM_DIR}/build/tools/clang/include"
 export PYTHONPATH=$PYTHONPATH:$CPYCPPYY_DIR:$CB_PYTHON_DIR
 ```
-If on MacOS you will also need the following envirnoment variable defined
+If on MacOS you will also need the following environment variable defined
 ```
 export SDKROOT=`xcrun --show-sdk-path`
 ```