unbelievable

adjective

un·​be·​liev·​able ˌən-bə-ˈlē-və-bəl 

: too improbable for belief

The plot is unreal and unbelievable.

also : of such a superlative degree as to be hard to believe

the destruction was unbelievable

made an unbelievable catch in center field

unbelievably

ˌən-bə-ˈlē-və-blē 

adverb

Synonyms of unbelievable

• incredible
• incredulous
• impossible
• unlikely

Examples of unbelievable in a Sentence

a completely unbelievable story about why there was lipstick on his collar

Recent Examples on the Web

Hill poured the putt in with ease and felt the embrace as the GB&I team completed a shocking, unbelievable comeback to win the Walker Cup. — Hugh Kellenberger, New York Times, 6 Sep. 2026

The Michigan Wolverines were beaten – and some would say literally – by Western Michigan on Saturday before one of the more unbelievable scenes in the sport's history unfolded. — Mark Harris Outkick, FOXNews.com, 6 Sep. 2026

Moments like these can definitely seem overwrought (and humor-wise, Moretti should probably refrain from the Viagra jokes), but they’re also handled with a fair amount of tongue-in-cheek tact despite some of the unbelievable circumstances. — Jordan Mintzer, HollywoodReporter, 5 Sep. 2026

That's the unbelievable streak that shocked grandparents in Folsom, California, where a trio of twin pregnancy announcements drew a reaction that went viral. — Kelsey Monstrola, USA Today, 1 Sep. 2026

Word History

First Known Use

1548, in the meaning defined above

Rhymes for unbelievable

• achievable
• believable
• conceivable
• perceivable
• receivable
• retrievable
• inconceivable
• irretrievable

Kids Definition

unbelievable

adjective

un·​be·​liev·​able ˌən-bə-ˈlē-və-bəl 

1

: too unlikely for belief

an unbelievable story

2

: very significant or impressive

made an unbelievable catch in center field

unbelievably

-blē 

adverb