unbelievable
/ˌʌnbɪˈliːvəbl̩/
Proposed by a contributor, not yet supported by evidence.
Also seen as: unbelievabler · unbelievablest
Sense 1
Meaning · English
Not to be believed.
Adjective
Examples
‘Come on, girls,’ said Steve, ‘be honest, we won.’ / ‘Yeah,’ said Raymond, ‘we let you off because you’re girls.’ / ‘You’re unbelievable,’ said Liz. / ‘Well, if we’re unbelievable,’ said Steve, ‘then you’re unbelievabler.’
Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-08-01)
Sources & notes
Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-08-01 via kaikki.org).
Sense 2
Meaning · English
Amazing, astonishing; so surprising that one is almost, or figuratively, unable to believe.
Adjective
Examples
The most unbelievable thing happened to me today!
Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-08-01)
Sources & notes
Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-08-01 via kaikki.org).
Common questions
What does “unbelievable” mean?
Not to be believed.
Is “unbelievable” formal or informal?
No register label has been reviewed yet — treat it as neutral and check the usage notes above.