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Definitions

unbelievable

[uhn-bi-lee-vuh-buhl] / ˌʌn bɪˈli və bəl /
ADJECTIVE
beyond the imagination
Synonyms
STRONGEST
astonishing implausible impossible improbable inconceivable incredible outlandish preposterous too much unimaginable unthinkable
WEAK
beyond belief cockamamie cockeyed doubtful dubious far-fetched fishy flaky flimsy for the birds full of holes harebrained incogitable kooky lamebrained open to doubt past belief phony questionable reaching scatterbrained screwy staggering suspect thick thin unconvincing unsubstantial weak won't hold water won't wash
Antonyms
STRONGEST
believable conceivable credible imaginable likely plausible possible reasonable tenable
WEAK
real

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

"Years ago people might not have thought that would happen - it's unbelievable."

From BBC • Apr. 29, 2026

Lockwood worked with a student this year who had all the stats —valedictorian, great extracurriculars and an unbelievable story.

From MarketWatch • Apr. 28, 2026

The first thing that had to go right was an unbelievable stroke of luck on the unluckiest night of Tatum’s life.

From The Wall Street Journal • Apr. 22, 2026

“What may have looked unbelievable turned out to be exactly that — and now those responsible are being held accountable,” state Insurance Commissioner Ricardo Lara said in a statement.

From Los Angeles Times • Apr. 18, 2026

All I kept thinking was, This is unbelievable.

From "When I Was the Greatest" by Jason Reynolds

Vocabulary lists containing unbelievable

Wow! Synonyms for "Amazing"

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