black light

American  

noun

1. invisible infrared or ultraviolet light.

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black light British  

noun

1. the invisible electromagnetic radiation in the ultraviolet and infrared regions of the spectrum

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black light Scientific  

1. Invisible ultraviolet radiation. Black light causes certain fluorescent materials to emit visible light.

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Etymology

Origin of black light

First recorded in 1925–30

Example Sentences

When they shine a black light on the coral, organic compounds in the coral cause it to fluoresce.

From Science Daily • Mar. 18, 2024

Then, she pulled out a black light, announcing that any lingering traces of gel would glow.

From New York Times • Jul. 25, 2023

One gallery in the Haring exhibition will be entirely bathed in black light, mimicking a show Haring held in the basement of New York’s Tony Shafrazi Gallery in 1982.

From Los Angeles Times • Oct. 12, 2022

The term “uranium glass” generally describes glass with uranium oxide, which glows under a black light.

From Washington Post • Oct. 11, 2022

I walk into the closet, where the black light has been replaced by a regular old bulb.

From "All The Bright Places" by Jennifer Niven