As I understand it, the glossary
directive creates hooks for each of the terms that can be easily referenced from anywhere in the documentation; and that is going to end up in an index somewhere, at least internally at build time.
To work around this, you could use a standard list of definitions:
term_1
definition for term_1
term_2
definition for term_2
These definitions will then only be written locally and not appear in the main index. See reST docs for more detail on the syntax.
If you want to explicitly include some terms in such a list, you could use the :index:
role.
:index:`term_3`
definition for an indexed term
and these terms will now appear in the index. However, unless it is very few terms, this is a clunky way of achieving what the glossary does for you; and loses out on the ability to use the cross-referencing (using syntax :term:`term_1`
).