IMPROBABLE

adj. doubtful, dubious, unlikely, questionable, unrealistic, far-fetched, remote, implausible, unthinkable, hard to believe or imagine, inconceivable, unbelievable, fanciful, incredible, ridiculous, ludicrous, absurd, crazy, mad, insane, wild, weird, peculiar, strange; impossible; Colloq fishy It is improbable that they will marry He gave the most improbable excuses.