heat island

American  

[heet ahy-luhnd] / ˈhit ˌaɪ lənd /

noun

1. an urban area having a higher average temperature than its rural surroundings owing to the greater absorption, retention, and generation of heat by its buildings, pavements, and human activities.

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heat-island British  

noun

1. meteorol the mass of air over a large city, characteristically having a slightly higher average temperature than that of the surrounding air

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Etymology

Origin of heat island

First recorded in 1960–65

Example Sentences

That is because of something called the urban heat island effect.

From BBC • Jun. 28, 2025

Urban green spaces provide shade for city dwellers facing rising temperatures brought on by climate change, but how much relief from the heat island effect do they provide when humidity is factored in?

From Science Daily • Nov. 14, 2024

Los Angeles is an urban heat island, which is made hotter than nearby rural areas by heat-trapping surfaces such as concrete, asphalt and some types of roofing.

From Los Angeles Times • Sep. 5, 2024

Ruese also suggested that local leaders improve urban infrastructure so that it reduces heat, and in particular the urban heat island effect.

From Salon • Apr. 15, 2024

The loss of unpaved space in the city could add to the urban heat island effect, absorbing rather than reflecting heat and contributing to higher temperatures than areas with more vegetation.

From Seattle Times • Feb. 24, 2024