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.
When such a wave washes over Earth, the radiation, consisting of X-ray and extreme ultraviolet light, interferes with radio transmissions, causing blackouts. Tereza Pultarova, Space.com, 17 Oct. 2025 First, ultraviolet light from the Sun strikes the water-ice rings, as do plasma clouds from meteoroid strikes. Big Think, 9 Oct. 2025 For one, ultraviolet light can suppress the immune system, Rahman says. Alexa Mikhail, Flow Space, 8 Oct. 2025 Research shows these differences may make the skin more vulnerable to damage from the sun's ultraviolet rays. Allison Aubrey, NPR, 6 Oct. 2025 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

Browse Nearby Words

Cite this Entry

“Ultraviolet.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ultraviolet. Accessed 21 Oct. 2025.

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

More from Merriam-Webster on ultraviolet

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