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Synonyms

unthinkable

American  
[uhn-thing-kuh-buhl] / ʌnˈθɪŋ kə bəl /

adjective

  1. inconceivable; unimaginable.

    the unthinkable size of the universe.

  2. not to be considered; out of the question.

    Such a suggestion is unthinkable.


noun

  1. something that cannot be conceived or imagined, as something too unusual, vague, or disagreeable.

    Today's unthinkables are tomorrow's realities.

unthinkable British  
/ ʌnˈθɪŋkəbəl /

adjective

  1. not to be contemplated; out of the question

  2. unimaginable; inconceivable

  3. unreasonable; improbable

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • unthinkability noun
  • unthinkableness noun
  • unthinkably adverb

Etymology

Origin of unthinkable

late Middle English word dating back to 1400–50; un- 1, thinkable

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

And all this is while he is attempting to implement new ideas and avoid the unthinkable scenario of dropping down into the Championship.

From BBC

It’s time to consider and stress-test what was once thought as unthinkable: Can a sustained breakdown of the “Magnificent Seven” and AI hyperscalers crash both the U.S. stock market and the economy?

From MarketWatch

Catalog sales command valuations unthinkable a decade ago.

From The Wall Street Journal

"Courbet deliberately created the painting for the private sphere; in the 19th century, a public presentation would have been unthinkable," says the exhibition notes.

From Barron's

He was going to be a big factor against the Toronto Blue Jays, until the unthinkable happened, and he immediately disappeared into his nightmare.

From Los Angeles Times