replicator
n. Any construct that acts to produce copies of
itself; this could be a living organism, an idea (see meme), a
program (see quine, worm, wabbit, fork bomb,
and virus), a pattern in a cellular automaton (see life,
sense 1), or (speculatively) a robot or nanobot. It is even
claimed by some that UNIX and C are the symbiotic halves
of an extremely successful replicator; see UNIX conspiracy.