impossible

adjective

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

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.
No sign yet of the Qualcomm fixes from last month which triggered a U.S. government update mandate for federal staff, with a deadline that was impossible to hit. Zak Doffman, Forbes.com, 8 July 2025 Nowadays, both men and women are serving faster than ever before, with players regularly reaching service speeds that were once thought to be nearly impossible. Ben Church, CNN Money, 8 July 2025 Booking commercial flights with connections to get back to California in time were looking impossible. Don Norcross, San Diego Union-Tribune, 7 July 2025 Suburban-style zoning has become widespread not just in suburbs proper, but also in core cities, many of which have adopted similar zoning codes that would have made their original growth and housing diversity impossible. Marina Bolotnikova, Vox, 7 July 2025 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

Browse Nearby Words

Cite this Entry

“Impossible.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/impossible. Accessed 13 Jul. 2025.

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

More from Merriam-Webster on impossible

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