(a.) Incapable of being conceived by the mind; not explicable by the human intellect\, or by any known principles or agencies; incomprehensible; as, it is inconceivable to us how the will acts in producing muscular motion.

a bit thick a bit thin absurd antic barred beguiling bewildering beyond belief closed-out contrary to reason doubtable doubtful dubious dubitable enigmatic exceptional excluded extraordinary fabulous fanciful fantastic fascinating hard of belief hard to believe hopeless implausible impossible incomprehensible incredible logically impossible marvelous mind-boggling miraculous not deserving belief not possible open to doubt open to suspicion outlandish overwhelming oxymoronic paradoxical passing belief passing strange phenomenal preposterous problematic prodigious prohibited puzzling questionable rare remarkable ridiculous ruled-out self-contradictory sensational staggering staggering belief strange striking stupendous suspect suspicious tall thick thin unaccountable unbelievable unconvincing unearthly unexpected ungodly unheard-of unimaginable unique unknowable unprecedented unthinkable unworthy of belief weak wonderful wondrous