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 third piece, particularly a Stanley Cup Final berth in 2028, feels wildly improbable. — Janson Duench, New York Times, 15 Sep. 2026

Portaluppi, whose architectural and interior designs rose to fame during the Art Deco and Rationalist periods, was known for his improbable structures and curious nooks and crannies filled with the sort of surprises that excite one’s inner child. — Sofia Celeste, Footwear News, 15 Sep. 2026

Coach Matt Potter led the Current on an improbable run to the 2022 NWSL championship. — Pj Green september 11, Kansas City Star, 11 Sep. 2026

However, an alliance of any kind between those parties is improbable and would be prone to instability. — ABC News, 7 Sep. 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