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Showing results for improbable. Search instead for improbabil.
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.

“People underestimate how improbable the improbable is,” says Christian Busch, a University of Southern California business-school professor and the author of “The Serendipity Mindset.”

From The Wall Street Journal • Apr. 4, 2026

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

From The Wall Street Journal • Apr. 3, 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

It would also make the scenario of a single Iranian missile hitting the site at the same time and causing such a high reported death toll highly improbable, an expert told BBC Verify.

From BBC • Mar. 9, 2026

No event in American history which was so improbable at the time has seemed so inevitable in retrospect as the American Revolution.

From "Founding Brothers: The Revolutionary Generation" by Joseph J. Ellis

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.