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. )
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.
Slegers described an "unbelievable performance" in the second leg because of the fightback Arsenal knew Chelsea would give.
From BBC • Apr. 1, 2026
A frustrated Russell, who finished fourth behind Piastri and Ferrari's Charles Leclerc, said over the radio "unbelievable" as he realised Antonelli would beat him for the second consecutive race.
From BBC • Mar. 29, 2026
There’s “tremendous, unbelievable uncertainty. That’s where we head from here,” he said.
From MarketWatch • Mar. 26, 2026
The Constitution is an unbelievable secular document to build a framework for ordered liberty.”
From The Wall Street Journal • Mar. 13, 2026
“Stimson told me that he wanted me to know about an immense project that was underway—-a project looking to the development of a new explosive of almost unbelievable power,” recalled Truman.
From "Bomb" by Steve Sheinkin
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.
