unbelievable

The word unbelievable describes something that is beyond understanding, like the idea, until the Middle Ages, that the earth might actually be round.

Unbelievable refers to something that seems incredible (Did you hear the story about the guy who was rescued after being stranded at sea for 6 months on a sailboat?), but it can also refer to something that's so unlikely, so improbable, that you're probably not going to be convinced by it (Hey, did you hear the story about the guy who was rescued after being stranded at sea for 6 months with only a log to keep him afloat?).

Definitions of unbelievable
1

adj beyond belief or understanding

Synonyms:
incredible
flimsy, unconvincing
not convincing
astounding, dumbfounding, dumfounding
bewildering or striking dumb with wonder
fabulous
barely credible
improbable, marvellous, marvelous, tall
too improbable to admit of belief
undreamed, undreamed of, undreamt, undreamt of, unimagined
not imagined even in a dream
incredulous
not disposed or willing to believe; unbelieving
implausible
having a quality that provokes disbelief
unthinkable
incapable of being conceived or considered
Antonyms:
believable, credible
capable of being believed
likely
within the realm of credibility
presumptive
affording reasonable grounds for belief or acceptance
plausible
apparently reasonable and valid, and truthful
thinkable
capable of being conceived or imagined or considered
show more antonyms...

adj having a probability too low to inspire belief

Synonyms:
improbable, unconvincing, unlikely
implausible
having a quality that provokes disbelief

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