ultraviolet

American  

[uhl-truh-vahy-uh-lit] / ˌʌl trəˈvaɪ ə lɪt /

adjective

1. beyond the violet in the spectrum, corresponding to light having wavelengths shorter than 4000 angstrom units.

2. pertaining to, producing, or utilizing light having such wavelengths.

   an ultraviolet lamp.

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noun

1. ultraviolet radiation.

ultraviolet British  

/ ˌʌltrəˈvaɪəlɪt /

noun

1. the part of the electromagnetic spectrum with wavelengths shorter than light but longer than X-rays; in the range 0.4 × 10 ^–6 and 1 × 10 ^–8 metres

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adjective

1.  UV.  of, relating to, or consisting of radiation lying in the ultraviolet

   ultraviolet radiation

ultraviolet Scientific  

/ ŭl′trə-vī′ə-lĭt /

1. Relating to electromagnetic radiation having frequencies higher than those of visible light but lower than those of x-rays, approximately 10 ¹⁵ –10 ¹⁶ hertz. Some animals, such as bees, are capable of seeing ultraviolet radiation invisible to the human eye.

2. See more at electromagnetic spectrum

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1. Ultraviolet light or the ultraviolet part of the spectrum.

2. See Note at infrared

Etymology

Origin of ultraviolet

First recorded in 1870–75; ultra- + violet

Compare meaning

How does ultraviolet compare to similar and commonly confused words? Explore the most common comparisons:

• infrared vs. ultraviolet

Explanation

Use the adjective ultraviolet to describe light with a wavelength that's less than visible light, but longer than x-rays. You can't see ultraviolet light. You might hear people talk about ultraviolet light as UV radiation — it's the part of sunlight that can give you a sunburn if you're exposed to it for too long. In physics, this kind of electromagnetic radiation is defined by how long its waves are. The word itself, ultraviolet, refers to the fact that its wavelength is shorter than the violet end of the spectrum of visible light. The Latin prefix ultra means "beyond."

Example Sentences

See Examples For:

ultraviolet

And a report this week that a Chinese company has made strides in ultraviolet lithography, a vital step in chip manufacturing, hit European tech giant ASML.

From The Wall Street Journal ● Jul. 29, 2026

For several months, the flare became brighter in ultraviolet light than the entire galaxy surrounding it.

From Science Daily ● Jul. 28, 2026

The declines followed losses by major US semiconductor stocks, after a report said a company was making specialised ultraviolet etching machines to boost China's chip industry.

From Barron's ● Jul. 28, 2026

Both the news of China mass-producing deep ultraviolet lithography machines and U.S. tech giants’ continued heavy spending weighed on market sentiment.

From The Wall Street Journal ● Jul. 28, 2026

It reads the ultraviolet barcode on the inside of everyone’s wrist and marks each internee as present, flashing our camp mug shots for a moment on the scanner’s screen.

From "Internment" by Samira Ahmed