WordNet (r) 3.0 (2006):

acronym
    n 1: a word formed from the initial letters of the several words
         in the name

The Free On-line Dictionary of Computing (19 January 2023):

acronym

    An identifier formed from some of the letters (often
   the initials) of a phrase and used as an abbreviation.

   A TLA is a meta-acronym, i.e. an acronym about acronyms.

   This dictionary (FOLDOC) contains a great many acronyms; see
   the contents page (/contents/all.html) for a list.

   (2014-08-14)