degree-day

noun

de·​gree-day di-ˈgrē-ˌdā How to pronounce degree-day (audio)
: a unit that represents one degree of difference from a given point (such as 65°) in the mean daily outdoor temperature and that is used especially to measure heat requirements

Word History

First Known Use

1832, in the meaning defined above

Time Traveler
The first known use of degree-day was in 1832

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Cite this Entry

“Degree-day.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/degree-day. Accessed 4 Mar. 2025.

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