solar constant

noun

: the quantity of radiant solar energy received at the outer layer of the earth's atmosphere that has a mean value of 1370 watts per square meter

Word History

First Known Use

1869, in the meaning defined above

Time Traveler
The first known use of solar constant was in 1869

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Cite this Entry

“Solar constant.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/solar%20constant. Accessed 6 Jul. 2026.

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