unthinkable

1 of 2

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

unthinkability

2 of 2

noun

un·​think·​abil·​i·​ty ¦ənˌthiŋkə¦bilətē How to pronounce unthinkability (audio)
: the quality or state of being unthinkable

Synonyms of unthinkable

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Adjective

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Examples of unthinkable in a Sentence

Adjective to most people it seemed unthinkable that such a gentle man could be guilty of such awful crimes
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Adjective
Just a few years ago, this scene of Jewish worshippers praying openly and vocally atop Jerusalem’s holiest of holy sites – known to Jews as the Temple Mount and to Muslims as the Al-Aqsa Mosque compound – would have been unthinkable. — Ilan Ben Zion, Christian Science Monitor, 14 Oct. 2026 But recent polling suggests Democrats could also capture the Senate, giving them full control of Congress — once an almost-unthinkable prospect. — Theodoric Meyer, Washington Post, 11 Oct. 2026 But empathy for them is still unthinkable for many in Israel, with memories raw. — Cara Anna, Los Angeles Times, 7 Oct. 2026 No team had ever made the playoffs after back-to-back 100-loss seasons, so to make it after three in a row was unthinkable, especially after one of their versatile pitchers was sidelined in spring training. — Don Riddell, CNN Money, 6 Oct. 2026 See All Example Sentences for unthinkable

Word History

First Known Use

Adjective

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 20 Oct. 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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