Btu

noun

ˌbē-ˌtē-ˈyü How to pronounce Btu (audio)
: british thermal unit

Word History

First Known Use

1882, in the meaning defined above

Time Traveler
The first known use of Btu was in 1882

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btry
Btu
BTW
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Cite this Entry

“Btu.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Btu. Accessed 9 Sep. 2025.

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Medical Definition

Btu

abbreviation
British thermal unit
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