ultraviolet

adjective

ul·​tra·​vi·​o·​let ˌəl-trə-ˈvī-(ə-)lət 

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

The top perovskite layer absorbs high-energy blue and ultraviolet light while allowing longer wavelengths to pass through to the bottom CIGS layer, which efficiently captures the remaining low-energy near-infrared light. — Mrigakshi Dixit, Interesting Engineering, 3 Sep. 2026

Such color variations are thought to be associated with camouflage, protection against parasites and ultraviolet radiation, and the effects of pleiotropic genes (genes that influence more than one, usually unrelated, physical trait or phenotype). — Encyclopedia Britannica, 3 Sep. 2026

Besides a basic image scan, the files also captured the images in the infrared and ultraviolet spectrums. — Dan Goodin, ArsTechnica, 2 Sep. 2026

Solar ultraviolet photons break apart bonds in molecules, creating radicals, which oxidize VOCs. — Michael A. Robinson, The Conversation, 25 Aug. 2026

Word History

First Known Use

1840, in the meaning defined at sense 1

Phrases Containing ultraviolet

• far-ultraviolet
• near-ultraviolet

Rhymes for ultraviolet

• inviolate
• violet

Kids Definition

ultraviolet

adjective

ul·​tra·​vi·​o·​let ˌəl-trə-ˈvī-ə-lət 

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 

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