unbelievable
Americanadjective
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too dubious or improbable to be believed.
an unbelievable excuse.
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so remarkable as to strain credulity; extraordinary.
the unbelievable fury of the storm; an unbelievable athlete.
adjective
Other Word Forms
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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un-
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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.
"It reminded me that we're capable of doing unbelievable things when how badly we want something matches and surpasses the difficulty of achieving it," he said.
From BBC ● Sep. 28, 2026
She also told the court that 400 people attended her husband's funeral, and said "he is missed by so many it was unbelievable".
From BBC ● Sep. 24, 2026
Sarah Prescott, the club's steward, described the evening as "overwhelming and unbelievable", thanking Jones for choosing the club to host the event.
From BBC ● Sep. 24, 2026
“I mean, it’s unbelievable how much of this is done with the pads of his fingers. And all of his fingerprints and thumbprints are crystal clear in the paint.”
From Los Angeles Times ● Sep. 22, 2026
I swallow, trying to get rid of the pressure in my throat, the unbelievable sadness that comes and comes as I look at it looking back at me.
From "The Knife of Never Letting Go" by Patrick Ness
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.
