The Collaborative International Dictionary of English v.0.48:

Pari- \Par"i-\ [L. par, paris, equal.]
   A combining form signifying equal; as, paridigitate,
   paripinnate.
   [1913 Webster]

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

Pari

    A system for symbolic mathematics,
   especially number theory.

   Version 1.37 for Unix, Macintosh, MS-DOS, Amiga.

   E-mail: .

   (ftp://math.ucla.edu/pub/pari).

   (1995-04-12)