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 plant is undergoing a massive underground construction project that will add ultraviolet disinfection and a chlorine contact basin, to the 90 year old facility. —Chase Hunter, Mercury News, 9 Sep. 2025

The gas is activated by the ultraviolet rays of the sun, making the tail glow in much the same way that black light causes phosphorescent paint to light up. —Joe Rao, Space.com, 8 Sep. 2025

When applied to animal skin in lab tests, that gel was found to block harmful ultraviolet rays as effectively as a conventional mineral- or chemical-based sunscreen with an SPF rating of about 30. —New Atlas, 6 Sep. 2025

Risk of the condition, which often results from overexposure to ultraviolet light, is seemingly growing in people under 40, the Mayo Clinic reports, especially among women. —Jay Stahl, USA Today, 5 Sep. 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