WordNet (r) 3.0 (2006):

functionality
    n 1: capable of serving a purpose well; "software with greater
         functionality"

The Free On-line Dictionary of Computing (30 December 2018):

functionality

    Waffle for "features" or "function".  The
   capabilities or behaviours of a program, part of a program, or
   system, seen as the sum of its features.  Roughly, "the
   things it can do".  Generally used in a comparative sense,
   e.g. "The latest update adds some useful functionality".

   (1997-07-14)