Add more entries to the glossary.
Written by Jeff Wheeler for GHOP.
diff --git a/Doc/library/codeop.rst b/Doc/library/codeop.rst
index 419e873..35430b4 100644
--- a/Doc/library/codeop.rst
+++ b/Doc/library/codeop.rst
@@ -43,8 +43,8 @@
:exc:`OverflowError` or :exc:`ValueError` if there is an invalid literal.
The *symbol* argument determines whether *source* is compiled as a statement
- (``'single'``, the default) or as an expression (``'eval'``). Any other value
- will cause :exc:`ValueError` to be raised.
+ (``'single'``, the default) or as an :term:`expression` (``'eval'``). Any
+ other value will cause :exc:`ValueError` to be raised.
.. warning::