The Collaborative International Dictionary of English v.0.48:
Imitator \Im"i*ta"tor\, n. [L.] One who imitates. [1913 Webster]WordNet (r) 3.0 (2006):
imitator n 1: someone who (fraudulently) assumes the appearance of another [syn: impersonator, imitator] 2: someone who copies the words or behavior of another [syn: copycat, imitator, emulator, ape, aper]