not genuine

counterfeit

(to make) (something) made or done in imitation of another thing in order to deceive

fake, simulated

a work of art etc that looks genuine but is not

false, imitation

trying to be like another

simulated, unoriginal

not real or genuine; to make fun of (a person, way of speaking etc) (especially by copying in an unkind or disrespectful way)

artificial, fake

not genuine or real

fake, false

to pretend (to be in the condition mentioned)

artificial, counterfeit

false; not genuine

counterfeit, fake

not authentic

counterfeit, fake