impossible

adjective

im·​pos·​si·​ble (ˌ)im-ˈpä-sə-bəl How to pronounce impossible (audio)
Synonyms of impossible
1
a
: incapable of being or of occurring
It's impossible to tell the future.
b
: felt to be incapable of being done, attained, or fulfilled : insuperably difficult
an impossible deadline
2
a
: extremely undesirable : unacceptable
in an impossible situation
b
: extremely awkward or difficult to deal with
The actor was impossible on the set.
impossibleness noun

Synonyms of impossible

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Examples of impossible in a Sentence

It's impossible to predict the future. The heavy rain made it impossible to see the road. It's physically impossible for a child to lift that much at once. It's virtually impossible to book a flight just before the holiday. These math problems are impossible! You refuse to help and then criticize me for not doing it right? You're impossible! My boss is just an impossible woman.
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.
On Monday, Zelenskyy said holding elections in Ukraine was impossible during war time, especially with new Russian tactics involving attacks day and night. — Arkansas Online, 13 Oct. 2026 But Qaddafi’s military forces were decisively defeated by Western airpower and his objective of crushing a popular uprising by force was rendered impossible. — Justin Bronk, Foreign Affairs, 13 Oct. 2026 Doomsday warnings about its risks have now become impossible to ignore, and protestors are taking to the streets to demand stronger safeguards. — Rumman Chowdhury, Vogue, 13 Oct. 2026 Nonetheless, EbonyLife Place London is a welcome addition to the UK cinema space, which is impossible to imagine without decades of important work on Black filmmaking in the UK, like Stephen Bourne’s essential book Black in the British Frame. — Zac Ntim, Deadline, 13 Oct. 2026 See All Example Sentences for impossible

Word History

Etymology

Middle English, from Anglo-French & Latin; Anglo-French, from Latin impossibilis, from in- + possibilis possible

First Known Use

14th century, in the meaning defined at sense 1a

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

Phrases Containing impossible

Rhymes for impossible

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Browse Nearby Words

impossibility
impossible
impossibly
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Cite this Entry

“Impossible.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/impossible. Accessed 14 Oct. 2026.

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Kids Definition

impossible

adjective
im·​pos·​si·​ble (ˈ)im-ˈpäs-ə-bəl How to pronounce impossible (audio)
1
a
: incapable of being or of occurring
b
: very difficult : hopeless
an impossible situation
2
: very bad or unpleasant
an impossible person
impossibly
-blē
adverb

Legal Definition

impossible

adjective
im·​pos·​si·​ble
: not possible : incapable of being done, attained, or fulfilled
a party's performance is impossible in part
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