unthinkable

adjective

un·​think·​able ˌən-ˈthiŋ-kə-bəl How to pronounce unthinkable (audio)
Synonyms of unthinkablenext
1
: not capable of being grasped by the mind
2
: being contrary to what is reasonable, desirable, or probable : being out of the question
unthinkability
ˌən-ˌthiŋ-kə-ˈbi-lə-tē How to pronounce unthinkable (audio)
noun
unthinkably
ˌən-ˈthiŋ-kə-blē How to pronounce unthinkable (audio)
adverb

Synonyms of unthinkable

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Examples of unthinkable in a Sentence

to most people it seemed unthinkable that such a gentle man could be guilty of such awful crimes
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Point is, that would have been unthinkable a year ago. — ABC News, 28 June 2026 Since then, mass shootings of this scale have been almost unthinkable. — Oscar Schwartz, New Yorker, 29 June 2026 There is also the once-unthinkable idea that Marathon could slowly shift its genre. — Paul Tassi, Forbes.com, 23 June 2026 Messi already has five, and someone reaching 10 doesn’t seem that unthinkable given the numbers the top players have put up so far. — Dan Santaromita, New York Times, 24 June 2026 See All Example Sentences for unthinkable

Word History

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of unthinkable was in the 15th century

Phrases Containing unthinkable

Rhymes for unthinkable

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Browse Nearby Words

unthinkability
unthinkable
unthinking
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Cite this Entry

“Unthinkable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unthinkable. Accessed 7 Jul. 2026.

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Kids Definition

unthinkable

adjective
un·​think·​able ˌən-ˈthiŋ-kə-bəl How to pronounce unthinkable (audio)
ˈən-
: not to be thought of or considered as possible
unthinkable cruelty

More from Merriam-Webster on unthinkable

Nglish: Translation of unthinkable for Spanish Speakers

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