Closes #19178: some more cross-references about packages in glossary. Patch by Berker Peksag.

Doc/glossary.rst

@@ -520,6 +520,8 @@ Glossary
       have a namespace containing arbitrary Python objects.  Modules are loaded
       into Python by the process of :term:`importing`.
 
+      See also :term:`package`.
+
    MRO
       See :term:`method resolution order`.
 
@@ -558,6 +560,8 @@ Glossary
       and specifically are not like a :term:`regular package` because they
       have no ``__init__.py`` file.
 
+      See also :term:`module`.
+
    nested scope
       The ability to refer to a variable in an enclosing definition.  For
       instance, a function defined inside another function can refer to
@@ -579,10 +583,12 @@ Glossary
       class`.
 
    package
-      A Python module which can contain submodules or recursively,
+      A Python :term:`module` which can contain submodules or recursively,
       subpackages.  Technically, a package is a Python module with an
       ``__path__`` attribute.
 
+      See also :term:`regular package` and :term:`namespace package`.
+
    parameter
       A named entity in a :term:`function` (or method) definition that
       specifies an :term:`argument` (or in some cases, arguments) that the
@@ -728,6 +734,8 @@ Glossary
       A traditional :term:`package`, such as a directory containing an
       ``__init__.py`` file.
 
+      See also :term:`namespace package`.
+
    __slots__
       A declaration inside a class that saves memory by pre-declaring space for
       instance attributes and eliminating instance dictionaries.  Though