a bit thick a bit thin absurd barred beyond belief closed-out contrary to reason doubtable doubtful dubious dubitable excluded extraordinary hard of belief hard to believe hopeless illogical implausible impossible improbable incomprehensible inconceivable incredible laughable logically impossible ludicrous mind-blowing mind-boggling not deserving belief not possible open to doubt open to suspicion oxymoronic paradoxical passing belief preposterous problematic prohibited questionable rare ridiculous ruled-out self-contradictory singular staggering belief suspect suspicious tall thick thin unacceptable unbelievable uncommon unconvincing unearthly ungodly unimaginable unique unlikely unordinary unusual unwonted unworthy of belief