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.
In the meantime, analysts say TSMC is adding tools like ASML's extreme ultraviolet lithography machines to existing factories to ramp up capacity. — Katie Tarasov, CNBC, 15 Oct. 2026 Scientists at the University of California, Riverside have taken a closer look at the chain of chemical reactions involved in destroying PFAS using ultraviolet light and sulfite. — Alexandra Harrell, Footwear News, 14 Oct. 2026 Research into how skin responds to ultraviolet radiation highlights the importance of managing sun exposure. — Rupendra Brahambhatt, Interesting Engineering, 10 Oct. 2026 Skin in the game Another entrant in last year's startup contest pitched a biotech company that helps people track their exposure to harmful ultraviolet rays and potentially detect skin cancer earlier. — Megan Cerullo, CBS News, 7 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 20 Oct. 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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