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

Examples of heat island in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
But in a heavily urbanized East Coast, especially New York City, temperatures could also feel hotter through the urban heat island effect. — Eduardo Cuevas, USA Today, 1 July 2026 Urban areas with a lot of pavement and buildings – known as heat islands – can have temperatures well above the city’s average. — Brian Bossak, The Conversation, 1 July 2026 As our research has shown, cities typically hold additional heat compared to surrounding rural locations because of the urban heat island. — Marshall Shepherd, Forbes.com, 6 June 2026 The heat spreads, contributing to what’s known as the urban heat island effect, said Vincent Cotrone, extension educator of urban forestry at Pennsylvania State University. — Aya Diab, Fortune, 23 May 2026 See All Example Sentences for heat island

Word History

First Known Use

1954, in the meaning defined above

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

Rhymes for heat island

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Browse Nearby Words

heating plant
heat island
heat lamp
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Cite this Entry

“Heat island.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/heat%20island. Accessed 14 Jul. 2026.

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