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.
Architecture is the one art, together with dance and theatre, that is unthinkable without space. — Scott Roxborough, HollywoodReporter, 6 Sep. 2026 Forged in crucibles of traumatic childhoods and unthinkable loss, both Batman and Alice seek to right wrongs that the criminal justice system won’t touch. — Erin Qualey, Vulture, 31 Aug. 2026 Duffy’s hubris of funding his travel show through his government position would have been unthinkable under any other administration, Republican or Democrat. — Lorraine Ali, Los Angeles Times, 26 Aug. 2026 At the end of last year, with the duo having won eight Grand Slams between them in a row, that data point looked unthinkable. — James Hansen, New York Times, 21 Aug. 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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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 Sep. 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
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