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 researchers then factored in the capability of the dust around the protostars to absorb the ultraviolet radiation and re-emit it at longer wavelengths of light. —Robert Lea, Space.com, 30 Nov. 2025

The breakdown can also be switched on or off using ultraviolet light or metal ions. —Aamir Khollam, Interesting Engineering, 28 Nov. 2025

When clouds get in the way, monarchs switch to a backup compass that relies on ultraviolet light to detect the angle of the Earth’s magnetic field. —Big Think, 27 Nov. 2025

Earth’s ozone layer acts as a planetary sunscreen, shielding humans, animals and plants from harmful ultraviolet radiation. —Daniel Peck, ABC News, 24 Nov. 2025

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