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

In Devon and Cornwall officers have also sprayed illegal riders and their bikes with SmartWater - a forensic marking product that contains a unique chemical code which becomes visible using ultraviolet light.

From BBC ● Sep. 17, 2026

Using observations of Venus together with radiative-transfer modeling, the scientists estimated how strongly the liquid inside the planet's cloud droplets would need to absorb ultraviolet and blue light to match what spacecraft and telescopes observe.

From Science Daily ● Sep. 13, 2026

RTX and Xcimer say they are developing a prototype for a pulsed ultraviolet laser system about the size of a shipping container that could be moved from place to place.

From The Wall Street Journal ● Sep. 10, 2026

Hubble and Webb observations showed that the nucleus shines more strongly in ultraviolet and infrared wavelengths than in visible light, which is also seen in distant little red dots.

From Science Daily ● Aug. 17, 2026

Even though it was a cloudy day, the vicious ultraviolet radiation at this altitude would render him snow-blind very quickly.

From "Into Thin Air" by Jon Krakauer