Source : Webster's Revised Unabridged Dictionary (1913)

Pirl \Pirl\, v. t. [Cf. {Purl}.]
   1. To spin, as a top.

   2. To twist or twine, as hair in making fishing lines.

Source : Free On-Line Dictionary of Computing

PIRL
     
        Pattern Information Retrieval Language.
     
        A language for {digraph} manipulation, embeddable in {Fortran}
        or {ALGOL}, for {IBM 7094}.
     
        ["PIRL - Pattern Information Retrieval Language",
        S. Berkowitz, Naval Ship Res Dev Ctr, Wash DC].
     
        (1994-11-29)