unbelievable
Americanadjective
-
too dubious or improbable to be believed.
an unbelievable excuse.
-
so remarkable as to strain credulity; extraordinary.
the unbelievable fury of the storm; an unbelievable athlete.
adjective
Other Word Forms
- unbelievability noun
- unbelievably adverb
Etymology
Origin of unbelievable
First recorded in 1540–50; un- 1 + believe ( def. ) + -able ( def. )
Explanation
The word unbelievable describes something that is beyond understanding, like the idea, until the Middle Ages, that the earth might actually be round. Unbelievable refers to something that seems incredible (Did you hear the story about the guy who was rescued after being stranded at sea for 6 months on a sailboat?), but it can also refer to something that's so unlikely, so improbable, that you're probably not going to be convinced by it (Hey, did you hear the story about the guy who was rescued after being stranded at sea for 6 months with only a log to keep him afloat?).
Vocabulary lists containing unbelievable
Wow! Synonyms for "Amazing"
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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.
“I love playing characters that are so unbelievable that they have to exist in a different way,” says Ortiz on a video call from New York.
From Los Angeles Times • Apr. 7, 2026
“It’s a lot of knowledge workers doing similar tasks with data, an unbelievable distribution network” that reaches institutional investors around the globe.
From Barron's • Apr. 3, 2026
There’s “tremendous, unbelievable uncertainty. That’s where we head from here,” he said.
From MarketWatch • Mar. 26, 2026
He added: "To think that my dad chose these numbers all those years ago before he died is just unbelievable."
From BBC • Mar. 23, 2026
The two figures on the hill opposite stopped dead in their tracks, listening to the unbelievable sound as it echoed around the quiet valley.
From "The Incredible Journey" by Sheila Burnford
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
