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 noun
unthinkably adverb

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.
The recent best supporting actress Oscar for Amy Madigan’s performance in Weapons, a horror film, would have been unthinkable not so long ago. Juan Claudio Matossian, Vanity Fair, 14 May 2026 While those brand elements are limited, the presence of ads was long unthinkable for the former premium cable network. Dade Hayes, Deadline, 13 May 2026 In 2020, five years after retiring from the ADL, Foxman did what once was unthinkable to him. Ron Kampeas, Sun Sentinel, 11 May 2026 Our-- our planes controlled the skies over Tehran, which was unthinkable before that. CBS News, 10 May 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

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Cite this Entry

“Unthinkable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unthinkable. Accessed 20 May. 2026.

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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