turncoat, benedict arnold, brutus, judas, judas iscariot, judas-like, quisling, trojan-horse, vicar of bray, apostate, archtraitor, backslider, betrayer, betraying, bolter, cockatrice, collaborationist, collaborator, conniver, conspirator , conspirer, convert, defector, deserter, double agent, double-crosser, double-crossing, double-dealer, fifth columnist, fifth-column, informer, intrigant, intriguer, machinator, mugwump, plotter, proselyte, quisling, quislingistic, rat, recidivist, recreant, renegade, renegado, renegate, reversionist, runagate, schemer, schismatic, seceder, secessionist, separatist, serpent, snake, spy, straggler, strikebreaker, tergiversant, tergiversator, timeserver, traitor, traitorous, treasonable, treasonist, treasonous, trimmer, turnabout, turntail, two-timing