a bit thick a bit thin absurd beyond belief doubtable doubtful dubious dubitable flimsy hard of belief hard to believe implausible improbable inconceivable incredible not deserving belief open to doubt open to suspicion passing belief preposterous problematic questionable ridiculous staggering belief suspect suspicious tall thick thin unbelievable unearthly ungodly unimaginable unsubstantial unthinkable unworthy of belief weak