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

A little over two years later, there’s no need to Google the 64-year-old coach who just finished leading the Hoosiers to an improbable 16-0 season and their first national championship in football. —Chuck Schilken, Los Angeles Times, 23 Jan. 2026

Set in an age when the Targaryen line still holds the Iron Throne and the last dragon has not yet passed from living memory, great destinies, powerful foes and dangerous exploits all await these improbable and incomparable friends. —Katie Campione, Deadline, 22 Jan. 2026

Nearly eight months after being thrust into the national spotlight following an improbable run to the NCAA Tournament, the Arkansas-Little Rock men's baseball team held its annual media day Tuesday ahead of the upcoming season. —Michael Harley, Arkansas Online, 21 Jan. 2026

The Heisman Trophy winner’s touchdown Monday night put an exclamation point on a 27-21 win over Miami that closed out an undefeated season and brought an improbable — maybe impossible? —Dallas Morning News, 20 Jan. 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