Update glossary.rst

[mg-lopez]

Really like the project, would love to contribute further. As mentioned in the docs, I read the user manual and edited the glossary to include expanded definitions and new terms that were not yet defined. 👍

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Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.80%. Comparing base (ec33cd0) to head (bacff6d).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6423   +/-   ##
=======================================
  Coverage   89.80%   89.80%           
=======================================
  Files          90       90           
  Lines       23752    23752           
  Branches     4418     4418           
=======================================
  Hits        21331    21331           
  Misses       1672     1672           
  Partials      749      749           

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