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

By studying them in ultraviolet light that terrestrial observatories can’t access because of Earth’s UV-blocking ozone layer, the project could literally shed more light on the still-mysterious details of stellar activity across the galaxy. —Joseph Howlett, Scientific American, 8 Apr. 2026

So far, the city has completed several major components of the Springbrook improvement project, including adding in an ultraviolet disinfection system that replaced the facility’s old chlorine disinfection system and adding new pumps at the influent pump station. —Carolyn Stein, Chicago Tribune, 8 Apr. 2026

Even on cloudy days or days spent mostly indoors, ultraviolet rays can still reach your skin and accelerate visible aging. —Kansas City Star, 7 Apr. 2026

One theory is that ultraviolet radiation from the sun may have been the key. —Jerome Groopman, New Yorker, 6 Apr. 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