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Synonyms

impossible

American  
[im-pos-uh-buhl] / ɪmˈpɒs ə bəl /

adjective

  1. An image of the word impossible as defined by not possible; unable to be, exist, happen, etc.

    not possible; unable to be, exist, happen, etc.

  2. unable to be done, performed, effected, etc..

    an impossible assignment.

  3. incapable of being true, as a rumor.

  4. not to be done, endured, etc., with any degree of reason or propriety.

    an impossible situation.

  5. utterly impracticable.

    an impossible plan.

  6. hopelessly unsuitable, difficult, or objectionable.

    Synonyms:
    unmanageable, intolerable, unbearable

impossible British  
/ ɪmˈpɒsəbəl /

adjective

  1. incapable of being done, undertaken, or experienced

  2. incapable of occurring or happening

  3. absurd or inconceivable; unreasonable

    it's impossible to think of him as a bishop

  4. informal intolerable; outrageous

    those children are impossible

"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

Etymology

Origin of impossible

First recorded in 1250–1300; Middle English word from Latin word impossibilis. See im- 2, possible

Explanation

Something that's impossible can't be done. If you want to stop eating donuts but you just can't, you might say it's impossible. If it's impossible, it cannot happen, or it doesn't exist. You might wish you could bring Abraham Lincoln back to life for a day so he could come to tea, but that's impossible. People use the word impossible to mean "out of reach" or "too hard to achieve." A terrible situation can be impossible, and so can a person who refuses to compromise or seems intent on making things difficult for everyone else.

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Vocabulary lists containing impossible

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.

See Examples For:

This scenario, he said, was “not impossible but also high enough to require an accommodative legislation environment and limited supply chain delays.”

From The Wall Street Journal ● Oct. 6, 2026

Spending on AI is becoming almost impossible for businesses to budget.

From MarketWatch ● Oct. 5, 2026

These Chargers have 13 games left, and identifying potential wins on the remaining schedule is a nearly impossible task.

From Los Angeles Times ● Oct. 5, 2026

Nigerian models donned outfits of seemingly impossible amounts of fabric folded and moulded into massive silhouettes, or overlapping in shingled, feather-like patterns.

From Barron's ● Oct. 3, 2026

“We agreed that it would be impossible for someone to reach you on purpose. Correct?”

From "The Brightwood Code" by Monica Hesse

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