PFY
= P =
phase
phage n.
A program that modifies other programs or
databases in unauthorized ways; esp. one that propagates a
virus or Trojan horse. See also worm,
mockingbird. The analogy, of course, is with phage viruses in
biology.
--The Jargon File version 4.3.1, ed. ESR, autonoded by rescdsk.