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

Relevance

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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Adjective
For one brief, improbable moment in the middle of the century, the arrangement very nearly worked. — Anthony Scaramucci, Fortune, 28 June 2026 The house also offers physical testament to the couple's improbable union. — Hamish Bowles, Vogue, 5 July 2026 Belgium also won in the round of 32 on Wednesday behind an improbable comeback over Senegal. — Andrew Greif, NBC news, 2 July 2026 To make the matchup even more improbable, the younger Muncy had missed more than a month with a left fifth metacarpal fracture, only being reactivated a few weeks before the Dodgers series. — Sean Campbell, Sacbee.com, 1 July 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 7 Jul. 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

More from Merriam-Webster on improbable

Nglish: Translation of improbable for Spanish Speakers

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