un·​think·​able | \ˌən-ˈthiŋ-kə-bəl \

Definition of unthinkable 

1 : not capable of being grasped by the mind

2 : being contrary to what is reasonable, desirable, or probable : being out of the question

Keep scrolling for more

Other Words from unthinkable

unthinkability \ˌən-​ˌthiŋ-​kə-​ˈbi-​lə-​tē \ noun
unthinkably \ˌən-​ˈthiŋ-​kə-​blē \ 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

Based on the past few Apple Cups, picking the Cougars to beat UW was unthinkable before the season began. The Seattle Times, "Pick ’em," 21 Nov. 2018 If the unthinkable were to happen, his insurance policy would help deal with it. Fox News, "Rep. Darrell Issa talks explosive Peter Strzok hearing," 15 July 2018 The unthinkable has happened - Dr. Pepper is putting Larry Culpepper on waivers. Ron Higgins, NOLA.com, "Dr. Pepper's Larry Culpepper won't return: Report," 22 May 2018 Though homosexuality had been decriminalized in Britain in 1967, being openly gay was still essentially unthinkable, especially for a prominent public figure. Karen Han, Vox, "How A Very English Scandal spins sensationalism into empathy," 7 July 2018 But as global warming rapidly brings the natural wonder to the brink of extermination, scientists are abandoning their hands-off approach in favor of a once-unthinkable strategy: a massive intervention to manipulate the natural balance of the reef. Evan Halper, latimes.com, "Racing to save Florida’s coral from climate change, scientists turn to a once-unthinkable strategy: ‘assisted evolution’," 9 July 2018 In recent years, Syria has experienced the most frequent use of chemical weapons anywhere globally in generations, raising fears that the world could become numbed to once-unthinkable atrocities. New York Times, "O.P.C.W., Chemical Weapons Watchdog, Gets Power to Assign Blame," 27 June 2018 Projects will range from parking experiments to public transit projects — a once unthinkable business move for a company that subsists on the profits of its trucks and SUVs. Tamara Warren, The Verge, "Inside Detroit’s crumbling train station that Ford plans to transform into a mobility lab," 20 June 2018 If he’s impeached, barring an economic collapse, he won’t be convicted in a million years and his re-election, once unthinkable, now has to be seen as likely. Andrew Sullivan, Daily Intelligencer, "Is the World Done With Liberal Democracy?," 1 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'unthinkable.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

See More

First Known Use of unthinkable

15th century, in the meaning defined at sense 1

Keep scrolling for more

Learn More about unthinkable

Share unthinkable

Statistics for unthinkable

Last Updated

4 Dec 2018

Look-up Popularity

Time Traveler for unthinkable

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

See more words from the same century

Keep scrolling for more

More Definitions for unthinkable



English Language Learners Definition of unthinkable

: impossible to imagine or believe : too bad or shocking to be thought of


un·​think·​able | \ˌən-ˈthiŋ-kə-bəl \

Kids Definition of unthinkable

: not to be thought of or considered as possible or reasonable “Impossible!” cried Mr. Wonka. “Unthinkable! … He could never be made into marshmallows!”— Roald Dahl, Charlie and the Chocolate Factory

Keep scrolling for more

More from Merriam-Webster on unthinkable

Rhyming Dictionary: Words that rhyme with unthinkable

Thesaurus: All synonyms and antonyms for unthinkable

Spanish Central: Translation of unthinkable

Nglish: Translation of unthinkable for Spanish Speakers

Comments on unthinkable

What made you want to look up unthinkable? Please tell us where you read or heard it (including the quote, if possible).


the figure or shape of a crescent moon

Get Word of the Day daily email!

Test Your Vocabulary

Late Autumn 2018 Words of the Day Quiz

  • frosted-autumn-leaves
  • Which is a synonym of yahoo?
Spell It

Can you spell these 10 commonly misspelled words?

Add Diction

Test Your Knowledge - and learn some interesting things along the way.


Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!