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Showing results for improbable. Search instead for reprobable.
Definitions

improbable

[im-prob-uh-buhl] / ɪmˈprɒb ə bəl /
ADJECTIVE
not likely
Synonyms
STRONGEST
fanciful implausible rare unbelievable unlikely
WEAK
doubtful dubious far-fetched flimsy hundred-to-one iffy inconceivable not expected outside chance questionable slim slim and none uncertain unconvincing unheard of unimaginable unsubstantial weak
Antonyms
STRONGEST
believable likely ordinary plausible probably real
WEAK
ostensible possible probable tenable

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

For decades, closure of the strait was regarded as something that was conceivable in theory, but operationally improbable in practice, Morgan Stanley noted.

From Barron's • Mar. 24, 2026

His grandfather Jerry Bush had coached at Nebraska, where in 1958 he authored an improbable victory over a Kansas team led by Wilt Chamberlain.

From The Wall Street Journal • Mar. 22, 2026

Before long, however, the two improbable friends have formed a siblinglike bond, sharing toys and teasing each other over who gets the most praise from Basma.

From The Wall Street Journal • Mar. 20, 2026

At least that’s what one improbable image fantasized in a recent slew of AI-generated “wedding photos” circulating online.

From Los Angeles Times • Mar. 17, 2026

I find it improbable, and ominous: first the retrospective, then the morgue.

From "Cat's Eye" by Margaret Atwood