Synonyms of improbable

improbable

adjective

(ˌ)im-ˈprä-bə-bəl 

as in unlikely

not likely to be true or to occur

it seems improbable that the two writers never met since they traveled in the same social circles

Synonyms & Similar Words

• unlikely
• doubtful
• questionable
• dubious
• odd
• impossible
• far-fetched
• flimsy
• bizarre
• implausible
• incredible
• inconceivable
• unapt
• unbelievable
• unthinkable
• unimaginable
• ridiculous
• absurd
• fantastic
• outlandish
• foolish
• nonsensical
• preposterous
• unreal
• insane
• crazy
• wild
• remote
• slight
• outside

Antonyms & Near Antonyms

• probable
• likely
• plausible
• possible
• conceivable
• potential
• credible
• earthly
• believable
• imaginable
• liable

Example Sentences

Recent Examples of improbable

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

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