Synonyms of improbable in English:

improbable


See definition of improbable

adjective

1‘it seemed improbable that the hot weather should continue much longer’

SYNONYMS
unlikely, not likely, doubtful, dubious, debatable, questionable, uncertain
difficult to believe, implausible, far-fetched, fanciful
unthinkable, inconceivable, unimaginable, unimagined, incredible
ANTONYMS

probable, certain

2‘the impression created by some advertisers is an improbable exaggeration’

SYNONYMS
inauthentic, unconvincing, unbelievable, incredible, ridiculous, absurd, preposterous
contrived, laboured, strained, forced
informal hard to swallow
ANTONYMS

believable, realistic