UV index

American  

noun

1. a measure, on a scale of 0 to 11, of the intensity of ultraviolet radiation from the sun at the sun's highest point on a particular day in a particular place, a higher number indicating greater exposure.

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UV index Scientific  

/ yo̅o̅′vē′ /

1. A scale ranging from 0 to 10, used to estimate the risk for sunburn in midday sunlight, with 0 indicating no risk and 10 indicating maximal risk. The UV index is effectively a rough measure of the amount of harmful ultraviolet radiation in the sunlight reaching the Earth's surface at a given location, given the time of year and current atmospheric conditions, expressed in terms of the risks that are associated with exposure to that amount of radiation.

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Example Sentences

The UV index was listed at 11, or extreme.

From Seattle Times • Jun. 23, 2023

The app also tracks the UV index, and it provides recommendations such as “avoid sun around noon, seek shade and use sunscreen,” when UV radiation from the sun is high.

From New York Times • Jun. 8, 2023

You should also avoid the sun’s harshest rays: If your phone’s weather app has a UV index, consult it, Holman says.

From Washington Post • Apr. 16, 2023

One of the major causes of skin cancer is a high UV index - experts recommend taking precautions for anything over level 3.

From BBC • Aug. 11, 2022

“Measures eighty values—temperature, UV index, dew point, you name it.”

From "A Walk in the Woods" by Bill Bryson