#12061: remove duplicate glossary entry.
diff --git a/Doc/glossary.rst b/Doc/glossary.rst
index 7822634..fa81144 100644
--- a/Doc/glossary.rst
+++ b/Doc/glossary.rst
@@ -392,26 +392,6 @@
value is assigned. ``**`` is used to accept or pass a dictionary of
keyword arguments. See :term:`argument`.
- key function
- A key function or collation function is a callable that returns a value
- used for sorting or ordering. For example, :func:`locale.strxfrm` is
- used to produce a sort key that is aware of locale specific sort
- conventions.
-
- A number of tools in Python accept key functions to control how elements
- are ordered or grouped. They include :func:`min`, :func:`max`,
- :func:`sorted`, :meth:`list.sort`, :func:`heapq.nsmallest`,
- :func:`heapq.nlargest`, and :func:`itertools.groupby`.
-
- There are several ways to create a key function. For example. the
- :meth:`str.lower` method can serve as a key function for case insensitive
- sorts. Alternatively, an ad-hoc key function can be built from a
- :keyword:`lambda` expression such as ``lambda r: (r[0], r[2])``. Also,
- the :mod:`operator` module provides three key function constuctors:
- :func:`~operator.attrgetter`, :func:`~operator.itemgetter`, and
- :func:`~operator.methodcaller`. See the :ref:`sortinghowto` for
- examples of how to create and use key functions.
-
lambda
An anonymous inline function consisting of a single :term:`expression`
which is evaluated when the function is called. The syntax to create