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.
About 10% of those rays are ultraviolet, or UV, light. Guy German, Fortune, 21 June 2026 About 10% of those rays are ultraviolet, or UV, light. Guy German, The Conversation, 18 June 2026 Any darkening of the skin occurs because ultraviolet radiation has triggered the body’s defense response. Kate Donnelly, Forbes.com, 23 June 2026 These symptoms are the body's immune response to dehydration and overheating, aimed at cooling the body and repairing any damage caused by ultraviolet radiation. Maggie O'Neill, Verywell Health, 18 June 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

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Cite this Entry

“Ultraviolet.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ultraviolet. Accessed 7 Jul. 2026.

Kids Definition

ultraviolet

adjective
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
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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