Synonyms of impossible

impossible

adjective

(ˌ)im-ˈpä-sə-bəl 

as in unlikely

incapable of being solved or accomplished

the seemingly impossible problem of world hunger

fitting everything in my backpack seemed an impossible task

Synonyms & Similar Words

• unlikely
• hopeless
• problematic
• impractical
• futile
• unattainable
• incredible
• insoluble
• unrealizable
• useless
• absurd
• undoable
• impracticable
• insuperable
• unsolvable
• insolvable
• infeasible
• questionable
• improbable
• unfeasible
• unworkable
• dubious
• inconceivable
• unusable
• unthinkable
• ridiculous
• unbelievable
• implausible
• unimaginable
• suspicious
• doubtful
• debatable
• suspect
• shaky
• disputable
• fishy
• far-fetched
• fantastic
• outlandish
• shady
• preposterous
• doubtable

Antonyms & Near Antonyms

• possible
• feasible
• achievable
• workable
• reasonable
• useful
• attainable
• practical
• soluble
• applicable
• practicable
• doable
• likely
• functional
• probable
• usable
• working
• serviceable
• realizable
• acceptable
• resolvable
• plausible
• conceivable
• credible
• believable

Example Sentences

Recent Examples of impossible

Fires that are nearly impossible to see from the air with the naked eye can stand out clearly through the camera. — Brian Maass, CBS News, 14 Aug. 2026

Now, with midterm elections less than three months away and campaigning poised to get underway in earnest, the gap has become impossible to ignore. — Josh Wingrove, Fortune, 14 Aug. 2026

Some possible/impossible threat is detected and no one is told anything about it. — Voice Of The People, New York Daily News, 14 Aug. 2026

Questions on the show are notoriously niche, which Eisenberg said made prep near impossible. — Heather Bushman, IndyStar, 14 Aug. 2026