unthinkable

[uhn-thing-kuh-buhl]

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

/ ʌnˈθɪŋkəbəl /

adjective

1. not to be contemplated; out of the question

2. unimaginable; inconceivable

3. unreasonable; improbable

Other Word Forms

• unthinkably adverb
• unthinkability noun
• unthinkableness noun

Word History and Origins

Origin of unthinkable¹

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

Example Sentences

The result is something that months ago was unthinkable.

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But for two years he’s managed to do the unthinkable — to keep his notoriously fractious caucus together, despite the razor-thin margins he’s been dealt.

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Like Rabbi Dunner, she believes British Jews are “thinking the unthinkable,” asking whether they ought to leave.

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Third, if we don’t enforce red lines, we open the door to the unthinkable.

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These names show that the unthinkable has become routine.

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Related Words

• absurd 
• extraordinary 
• illogical 
• implausible 
• impossible 
• improbable 
• inconceivable 
• preposterous 
• rare 
• unbelievable 
• uncommon 
• unimaginable 
• unlikely 
• unreasonable