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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.

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

"Her strength was unbelievable and she was more worried about us than herself."

From BBC • Apr. 20, 2026

“I’m just not threatened by it . . . Ten years ago, I would have needed to engage a visual effects house at an unbelievable cost to come up with this stuff,” he said.

From Salon • Apr. 17, 2026

“It was unbelievable that you got to bring the trophy back to the hotel. That’s what I remember: taking those moments and enjoying them with the people that I really care about.”

From Los Angeles Times • Apr. 6, 2026

He was half lying across the child as the ground shook to the unbelievable roar.

From "Atonement" by Ian McEwan

Vocabulary lists containing unbelievable

Wow! Synonyms for "Amazing"

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