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

Extreme ultraviolet systems, or EUVs, are ASML’s most advanced machines that are used to print the most intricate layers on chips.

From The Wall Street Journal ● Jul. 15, 2026

Red dwarfs, however, can produce powerful flares that imitate the ultraviolet signal of a white dwarf, making confirmation more difficult.

From Science Daily ● Jul. 15, 2026

As space stretches over billions of years, the light from these distant quasars shifts from ultraviolet into the near infrared.

From Science Daily ● Jul. 9, 2026

There are several variables when it comes to up-front and ongoing costs of using grass, especially in domed stadiums where permanent ultraviolet grow-light systems, drainage and irrigation would need to be installed.

From Los Angeles Times ● Jul. 9, 2026

Perhaps it is due to complex brightly colored organic molecules produced when ultraviolet light from the Sun breaks down the methane, ammonia, and water in the Jovian atmosphere and the molecular fragments recombine.

From "Cosmos" by Carl Sagan