diff --git a/docs/design_doc.md b/docs/design_doc.md
index a46d41f8..c52eaf1e 100644
--- a/docs/design_doc.md
+++ b/docs/design_doc.md
@@ -307,7 +307,7 @@ Since elements are allowed to have only (a subset of the) c, x, y, z axes and mu
 
 In details:
 
-- we don't need to specify the intrinsic coordinate systems, these are inferred from the element schema
+- we don't need to specify the intrinsic coordinate systems, these are inferred from the element schema (e.g., for an `axes` array with two axes named "y" and "x", the intrinsic coordinate system would be named "yx")
 - each element MAY have a transformation mapping them to one or more extrinsic coordinate systems
 
 Each coordinate system