convincing Antonyms

unconvincing makeshift speculative spurious squaring theoretic theoretical uncalled-for unconceivable undreamed unearned unfounded unreal unreasonable unreasoned specious sophistic slavish mythical mythologic negotiable papery phantasmal powdery preposterous qualmish questionable reasonless refutable resigned shaky unreliable unsound beyond belief unsupported iffy imprecise off-colour unsatisfying trumped-up uncompelling uncorroborated unpersuasive unsubstantiated untested wild-eyed unthinkable chancy unpardonable untrue