improbable

1 of 2

adjective

im·​prob·​a·​ble (ˌ)im-ˈprä-bə-bəl How to pronounce improbable (audio)
-ˈpräb-bəl
Synonyms of improbable
: unlikely to be true or to occur
an improbable story
also : unlikely but real or true
their improbable come-from-behind victory
improbability
(ˌ)im-ˌprä-bə-ˈbi-lə-tē How to pronounce improbable (audio)
noun
improbably
(ˌ)im-ˈprä-bə-blē How to pronounce improbable (audio)
-ˈpräb-blē
adverb

improbability

2 of 2

noun

im·​probability (¦)im How to pronounce improbability (audio)
əm+
1
: the quality or state of being improbable
questioned the improbability of a nuclear accident
2
: something improbable

Synonyms of improbable

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Adjective

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Examples of improbable in a Sentence

Adjective The team made an improbable comeback. it seems improbable that the two writers never met since they traveled in the same social circles
Recent Examples on the Web
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Adjective
The truth, that these small animals were traveling thousands of miles across the planet, must once have seemed just as improbable. — Amy L. Scarpignato, The Conversation, 16 Oct. 2026 Instead, Nick Sirianni gifted Jacksonville a live return, setting up an improbable walk-off win. — Alejandro Avila Outkick, FOXNews.com, 13 Oct. 2026 Seven months removed from their improbable appearance in February’s Super Bowl, the New England Patriots looked anything but super. — Peter Sblendorio, New York Daily News, 13 Oct. 2026 The Jaguars pulled off an improbable 19-17 victory on Cam Little's 57-yard field goal as time expired at Tottenham Hotspur Stadium on Sunday. — CBS News, 12 Oct. 2026 See All Example Sentences for improbable

Word History

Etymology

Adjective

Middle French or Latin; Middle French, from Latin improbabilis, from in- + probabilis probable

First Known Use

Adjective

1598, in the meaning defined above

Time Traveler
The first known use of improbable was in 1598

Rhymes for improbable

See All Rhymes for improbable

Browse Nearby Words

improbability
improbable
improbation
See all Nearby Words

Cite this Entry

“Improbable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/improbable. Accessed 20 Oct. 2026.

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Kids Definition

improbable

adjective
im·​prob·​a·​ble (ˈ)im-ˈpräb(-ə)-bəl How to pronounce improbable (audio)
: not probable : unlikely to be true or to occur
improbability
(ˌ)im-ˌpräb-ə-ˈbil-ət-ē How to pronounce improbable (audio)
noun
improbably
(ˈ)im-ˈpräb(-ə)-blē How to pronounce improbable (audio)
adverb
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