WordNet (r) 3.0 (2006):

four flush
    n 1: the act of bluffing in poker; deception by a false show of
         confidence in the strength of your cards [syn: bluff,
         four flush]

Moby Thesaurus II by Grady Ward, 1.0:

27 Moby Thesaurus words for "four flush":
   act, act a part, affect, assume, bluff, counterfeit, cover up,
   dissemble, dissimulate, fake, feign, gammon, let on, let on like,
   make a pretense, make as if, make believe, make like, play,
   play a part, play possum, playact, pretend, profess, put on, sham,
   simulate