unthinkable
Americanadjective
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inconceivable; unimaginable.
the unthinkable size of the universe.
-
not to be considered; out of the question.
Such a suggestion is unthinkable.
noun
adjective
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not to be contemplated; out of the question
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unimaginable; inconceivable
-
unreasonable; improbable
Other Word Forms
Derived Forms
Inflected Forms
Nouns
Etymology
Origin of unthinkable
late Middle English word dating back to 1400–50; see origin at un- 1, thinkable
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.
Tuchel's strict refusal to operate a star system, as well as the emergence of Aston Villa's outstanding Rogers, has made Bellingham's place the subject of intense debate, a notion unthinkable after Euro 2024.
From BBC • Jun. 17, 2026
This has made unthinkable a conventional armored thrust to Tehran, along the lines of the 2003 U.S. invasion of Iraq.
From The Wall Street Journal • Jun. 10, 2026
E. Jean Carroll achieved the unthinkable and might end up paying a price for it.
From Slate • Jun. 1, 2026
But it turns out what was really unthinkable was Ferrell getting all 10 nuggets down the hatch before the Six Flags ride was over.
From Los Angeles Times • May 29, 2026
It was unthinkable that Stargirl could survive—or at least survive unchanged—among us.
From "Stargirl" by Jerry Spinelli
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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.