impossibility

noun

im·​pos·​si·​bil·​i·​ty (ˌ)im-ˌpä-sə-ˈbi-lə-tē How to pronounce impossibility (audio)
1
: the quality or state of being impossible
the impossibility of knowing the future
2
: something impossible
The snowstorm made travel an impossibility.

Examples of impossibility in a Sentence

The blizzard made travel an impossibility. the impossibility of knowing what the future will bring
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.
If the Heat loses to Philadelphia on Monday and at home to Boston on Wednesday, Miami’s already remote chances of moving to fifth or sixth will move closer to a mathematical impossibility. Barry Jackson, Miami Herald, 30 Mar. 2026 Pain has haunted Tiger Woods even more than the knowledge that something that once seemed an eventuality – breaking Jack Nicklaus’ record for the most major championships won, 18 – now was an impossibility. Cnn.com Wire Service, Mercury News, 30 Mar. 2026 Pain has haunted Tiger Woods even more than the knowledge that something that once seemed an eventuality – breaking Jack Nicklaus’ record for the most major championships won, 18 – now was an impossibility. Kyle Feldscher, CNN Money, 28 Mar. 2026 In a way, the impossibility of Proxi was the point. Eric Boodman, Vulture, 25 Mar. 2026 See All Example Sentences for impossibility

Word History

First Known Use

14th century, in the meaning defined at sense 1

Time Traveler
The first known use of impossibility was in the 14th century

Browse Nearby Words

Cite this Entry

“Impossibility.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/impossibility. Accessed 31 Mar. 2026.

Kids Definition

impossibility

noun
im·​pos·​si·​bil·​i·​ty (ˌ)im-ˌpäs-ə-ˈbil-ət-ē How to pronounce impossibility (audio)
plural impossibilities
1
: the quality or state of being impossible
2
: something impossible

Legal Definition

impossibility

noun
im·​pos·​si·​bil·​i·​ty
plural impossibilities
1
: the quality or state of being impossible
also : the affirmative defense that something (as performance) is impossible
2
: something impossible
3
: impossibility of performance in this entry
factual impossibility
: impossibility based on factual circumstances
specifically : a partial defense to criminal liability based on the incompletion of an intended criminal act

Note: Factual impossibility is not a complete defense and does allow prosecution for attempt or for another inchoate offense. For example, if the defendant constructed a bomb that failed to explode, factual impossibility would be a defense against murder charges, but not attempted murder.

impossibility of performance
: a doctrine in contract law that a party may be released from liability for breach of contract for failing to perform an obligation that is rendered impossible by uncontrollable circumstances (as death or failure of the means of delivery)
: a defense to breach of contract or a basis for release from contractual obligations because of impossibility of performance compare frustration, impracticability
legal impossibility
: impossibility based on or with reference to a law
specifically : a complete defense to criminal liability based on the commitment of acts that are not criminal or illegal

Note: Legal impossibility is founded on the principle that an act is not a crime unless there is a law prohibiting it.

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