WordNet sense 1 (a person who makes deceitful pretenses):

fake, faker, fraud, imposter, impostor, pretender, pseudo, pseud, shammer, role player

WordNet sense 2 (something that is a counterfeit; not what it seems to be):

postiche

WordNet sense 3 (make a pretence of):

assume, feign, simulate

WordNet sense 4 (adopted in order to deceive):

assumed, fictitious, fictive, false, pretended, put on

WordNet sense 5 (not genuine; imitating something superior):

counterfeit

WordNet sense 6 (make believe with the intent to deceive):

affect, dissemble, pretend, affect