heat island

noun

plural heat islands
: an urban area that experiences higher atmospheric temperatures than the surrounding environment (as due to having less greenery and more structures that absorb and retain heat)
often used before another noun
factors that contribute to a heat island effect

Word History

First Known Use

1954, in the meaning defined above

Time Traveler
The first known use of heat island was in 1954

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Cite this Entry

“Heat island.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/heat%20island. Accessed 15 Nov. 2025.

Last Updated: - Entry added
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