WordWeb Online

1. Marked by or given to imitation
   "acting is an imitative art"; "man is an imitative being"
    
2. (of words) formed in imitation of a natural sound
   "onomatopoeic words are imitative of noises";
   - echoic, onomatopoeic, onomatopoeical, onomatopoetic
    
3. Not genuine; imitating something superior
   "imitative emotion";
   - counterfeit

See also: apelike, apish, artificial, assumed, bad, base, bogus, cod [Brit, informal], fake, false, fictitious, fictive, forged, inauthentic, insincere, mimetic, mimic, mock, ostensible, ostensive, parrot-fashion [Brit], parrotlike, phoney, phony [N. Amer], pinchbeck, pretended, pseudo, put on, sham, simulated, spurious, synthetic, unauthentic, unreal

Antonym: nonimitative