Incredible

(a.) Not credible; surpassing belief; too extraordinary and improbable to admit of belief; unlikely; marvelous; fabulous.

Thesaurus Entries

a bit thick, a bit thin, absurd, amazing, antic, appalling, astonishing, astounding, awe-inspiring, awesome, beguiling, bewildering, beyond belief, bizarre, cockamamie, conspicuous, crazy, doubtable, doubtful, dubious, dubitable, egregious, enigmatic, exceptional, extraordinary, extravagant, fabulous, fanciful, fantastic, fascinating, fictitious, flimsy, foolish, formidable, grotesque, hard of belief, hard to believe, hardly possible, high-flown, humongous, implausible, impossible, improbable, incomprehensible, inconceivable, laughable, ludicrous, marked, marvelous, miraculous, monstrous, more than doubtful, mythical, nonsensical, not deserving belief, notable, noteworthy, noticeable, of mark, open to doubt, open to suspicion, outlandish, outrageous, outre, outstanding, passing belief, passing strange, phenomenal, poppycockish, preposterous, problematic, prodigious, puzzling, questionable, rare, remarkable, ridiculous, sensational, signal, staggering belief, strange, striking, stupendous, superior, suspect, suspicious, tall, thick, thin, tremendous, unaccountable, unbelievable, uncommon, unconvincing, unearthly, unexpected, ungodly, unheard-of, unimaginable, unique, unlikely, unprecedented, unpromising, unreal, unrealistic, unsubstantial, untenable, unthinkable, unworthy of belief, weak, weird, wild, wonderful, wondrous