convincing Antonyms

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