ultraviolet

adjective

ul·​tra·​vi·​o·​let ˌəl-trə-ˈvī-(ə-)lət How to pronounce ultraviolet (audio)
1
: situated beyond the visible spectrum at its violet end
—used of radiation having a wavelength shorter than wavelengths of visible light and longer than those of X-rays
2
: relating to, producing, or employing ultraviolet radiation
ultraviolet noun

Examples of ultraviolet in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The plan was to combine that map with a map of the ultraviolet radiation that heats the ISM up. — Perri Thaler, Quanta Magazine, 30 Oct. 2026 Your Cells Are Protected by Antioxidant Effects Our bodies are exposed to highly reactive free radicals through normal metabolism and environmental exposures such as pollution and ultraviolet light. — Pamela Assid Woughter, Verywell Health, 24 Oct. 2026 To optimize the conditions, ultraviolet lights have been part of the regular treatment plan at the stadium to lengthen the growing season. — Chicago Tribune, 22 Oct. 2026 These compounds quickly destroy the stratospheric ozone, the gas that filters out harmful ultraviolet radiation from the sun. — Robin George Andrews, Scientific American, 20 Oct. 2026 See All Example Sentences for ultraviolet

Word History

First Known Use

1840, in the meaning defined at sense 1

Time Traveler
The first known use of ultraviolet was in 1840

Phrases Containing ultraviolet

Rhymes for ultraviolet

See All Rhymes for ultraviolet

Browse Nearby Words

ultraviolence
ultraviolet
ultraviolet spectrum
See all Nearby Words

Cite this Entry

“Ultraviolet.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ultraviolet. Accessed 2 Nov. 2026.

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Kids Definition

ultraviolet

adjective
ul·​tra·​vi·​o·​let ˌəl-trə-ˈvī-ə-lət How to pronounce ultraviolet (audio)
1
: located beyond the visible spectrum at its violet end and having a wavelength shorter than those of visible light but longer than those of X-rays
2
: relating to, producing, or using ultraviolet radiation
ultraviolet noun

Medical Definition

ultraviolet

1 of 2 adjective
ul·​tra·​vi·​o·​let ˌəl-trə-ˈvī-(ə-)lət How to pronounce ultraviolet (audio)
1
: situated beyond the visible spectrum at its violet end
—used of radiation having a wavelength shorter than wavelengths of visible light and longer than those of X-rays
2
: relating to, producing, or employing ultraviolet radiation

ultraviolet

2 of 2 noun
: ultraviolet radiation
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