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

The Man of Steel was the first superhero to enter pop culture, helping boost the copy’s value among collectors, alongside its improbable backstory, Allen said. —Jack Brook, Fortune, 25 Nov. 2025

The Man of Steel was the first superhero to enter pop culture, helping boost the copy's value among collectors, alongside its improbable backstory. —Adeola Adeosun, MSNBC Newsweek, 25 Nov. 2025

Dallas is lucky that the miscues did not cost the team on the way to an improbable win. —Nick Harris, Fort Worth Star-Telegram, 24 Nov. 2025

The surprise felt even more improbable because Shawna had been juggling personal challenges that made travel difficult, adding to her emotional reaction. —Ashley Vega, PEOPLE, 21 Nov. 2025

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