improbable

adjective

im·​prob·​a·​ble (ˌ)im-ˈprä-bə-bəl 

-ˈpräb-bəl

: 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 

noun

improbably

(ˌ)im-ˈprä-bə-blē 

-ˈpräb-blē

adverb

Synonyms of improbable

• unlikely

Examples of improbable in a Sentence

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

But as the team looks to fortify its roster in the middle of an improbable contention surge, fans might be thinking about some of the transaction miscues the team has had in previous years. — Peter Chawaga, Forbes.com, 2 Aug. 2026

The 2017 legislation also set a goal reaching 90% adequacy statewide by 2027 — a target many advocates even then viewed as improbable, if not impossible. — Kate Armanini, Chicago Tribune, 1 Aug. 2026

But the request only seemed fitting, after the Minnesota Twins utilityman forecast one of the more improbable moments in team history. — Dan Hayes, New York Times, 31 July 2026

In the ninetieth minute, with Argentina hanging on, but retaining hope of an improbable victory, Messi was body-blocked by Aymeric Laporte, a Spain defender, and thrown to the floor. — Sam Knight, New Yorker, 20 July 2026

Word History

Etymology

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

First Known Use

1598, in the meaning defined above

Rhymes for improbable

• probable

Kids Definition

improbable

adjective

im·​prob·​a·​ble (ˈ)im-ˈpräb(-ə)-bəl 

: not probable : unlikely to be true or to occur

improbability

(ˌ)im-ˌpräb-ə-ˈbil-ət-ē 

noun

improbably

(ˈ)im-ˈpräb(-ə)-blē 

adverb