bpo-33459: Fix "tuple displays" term in Expressions.rst (GH-6760) (GH-15940)

https://bugs.python.org/issue33459

Automerge-Triggered-By: @matrixise
(cherry picked from commit dc269971091710563a0d730a0d4b084901826c15)

Co-authored-by: Andre Delfino <adelfino@gmail.com>
diff --git a/Doc/reference/expressions.rst b/Doc/reference/expressions.rst
index ee13c5f..73a2f27 100644
--- a/Doc/reference/expressions.rst
+++ b/Doc/reference/expressions.rst
@@ -148,9 +148,8 @@
 tuple may or may not yield the same object).
 
 .. index::
-   single: comma; tuple display
-   pair: tuple; display
-   single: , (comma); tuple display
+   single: comma
+   single: , (comma)
 
 Note that tuples are not formed by the parentheses, but rather by use of the
 comma operator.  The exception is the empty tuple, for which parentheses *are*
@@ -1822,7 +1821,8 @@
 | ``x[index]``, ``x[index:index]``,             | Subscription, slicing,              |
 | ``x(arguments...)``, ``x.attribute``          | call, attribute reference           |
 +-----------------------------------------------+-------------------------------------+
-| ``(expressions...)``,                         | Binding or tuple display,           |
+| ``(expressions...)``,                         | Binding or parenthesized            |
+|                                               | expression,                         |
 | ``[expressions...]``,                         | list display,                       |
 | ``{key: value...}``,                          | dictionary display,                 |
 | ``{expressions...}``                          | set display                         |