diff --git a/yaml.html.markdown b/yaml.html.markdown
index 2bb35d42..6901695c 100644
--- a/yaml.html.markdown
+++ b/yaml.html.markdown
@@ -165,7 +165,7 @@ other_anchor: *anchor_name
 base: &base
   name: Everyone has same name
 
-# The regexp << is called 'Merge Key Language-Independent Type'. It is used to
+# The expression << is called 'Merge Key Language-Independent Type'. It is used to
 # indicate that all the keys of one or more specified maps should be inserted
 # into the current map.
 # NOTE: If key already exists alias will not be merged