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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.

“Meme” traders had a hand in the improbable three-year septupling of bitcoin.

From The Wall Street Journal • Apr. 3, 2026

Then came the most improbable comeback in college basketball’s modern history.

From The Wall Street Journal • Mar. 30, 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

"Switzerland has nurtured many unexpected good things -- Albert Einstein's physics, the world economy, and the cuckoo clock leap to mind -- and is again helping the world appreciate improbable people and ideas."

From Barron's • Mar. 10, 2026

He hoped the birds had already sensed that something awful was about to happen and had flown away, though it seemed improbable.

From "Hoot" by Carl Hiaasen