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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.

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

From The Wall Street Journal • Mar. 30, 2026

The then 19-year-old scored seven goals in 21 appearances to help Rovers to automatic promotion, including the seventh goal in their improbable 7-0 final-day win over Scunthorpe.

From BBC • Mar. 30, 2026

But the great irony of a victory sealed by his improbable 2-pointer was that High Point only found itself in a position to win because of Johnston’s outrageous strategy for shooting threes.

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 knew that the Tiger General was the head of the brotherhood, but how he had gotten that other name—as improbable as it sounded—I did not know.

From "Dragonwings" by Laurence Yep

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