air conditioner

noun

: a machine that is used to cool and dry the air in a building, room, etc. : an appliance used for air conditioning

Word History

First Known Use

1908, in the meaning defined above

Time Traveler
The first known use of air conditioner was in 1908

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Cite this Entry

“Air conditioner.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/air%20conditioner. Accessed 18 Dec. 2025.

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