impossible

adjective

im·​pos·​si·​ble (ˌ)im-ˈpä-sə-bəl How to pronounce impossible (audio)
Synonyms of impossiblenext
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

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.
Travel could be very difficult to impossible. Ca Weather Bot, Sacbee.com, 21 Dec. 2025 As a result, effective navigation became impossible. Bojan Stojkovski, Interesting Engineering, 20 Dec. 2025 Replacing Hoover will be a daunting task, but not impossible. Steven Johnson, Fort Worth Star-Telegram, 20 Dec. 2025 Psychological and Social Effects Growing up in a society with consistent access to a selective reality on social media that often doesn’t reflect true reality, can result in pressures, expectations, and beliefs that are difficult or impossible to realize, says Biller. Sherri Gordon, Parents, 20 Dec. 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 21 Dec. 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

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