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 latter seems annoyingly improbable these days, given the sheer amount of content spend Netflix now puts out every year ($20 billion in 2026). — Paul Tassi, Forbes.com, 7 Aug. 2026

Trump’s improbable rise to political dominance, which polls failed to register in the lead-up to the 2016 election, is a clear testament to that reality, and now Michigan has shown how similar head fakes can occur on the left. — The Editorial Board, Chicago Tribune, 6 Aug. 2026

Nevertheless, Richmond’s improbable comeback dazzled fans and turned its players into legends. — Rachel Labonte, Entertainment Weekly, 5 Aug. 2026

Like a certain hero of Greek myth and big-screen blockbuster, the Etna of Yoon's title is the veteran of a catastrophic war, scarred in body and mind, dogged in pursuit of an improbable homecoming. — Colin Dwyer, NPR, 4 Aug. 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