infrared

adjective

in·​fra·​red ˌin-frə-ˈred 

-(ˌ)frä-,

-fə-

1

: situated outside the visible spectrum at its red end

—used of radiation having a wavelength between about 700 nanometers and 1 millimeter

2

: relating to, producing, or employing infrared radiation

infrared therapy

3

: sensitive to infrared radiation

infrared sensors that detect body heat

infrared noun

Examples of infrared in a Sentence

Recent Examples on the Web

Greene’s Introduction explains that collecting low-wavelength, infrared information requires significant mirror real estate (hence the larger mirror). —Rebecca Coffey, Forbes, 27 Nov. 2024

The new cameras offer two types of view: a natural, naked eye-type of view and an infrared perspective of the landscape. —Dan Perry, Newsweek, 26 Nov. 2024

There are some hair tools on the market that boast infrared light technology, but these lights have no drying effect on the hair. —Sophia Panych, Allure, 24 Nov. 2024

Snakes see infrared light, birds and reindeer see ultraviolet light, and dolphins use sound waves to navigate underwater. —Melanie Stetson Freeman, The Christian Science Monitor, 22 Nov. 2024

Word History

First Known Use

1881, in the meaning defined at sense 1

Phrases Containing infrared

• far-infrared
• near-infrared

Kids Definition

infrared

adjective

in·​fra·​red ˌin-frə-ˈred 

-(ˌ)frä-

: being, relating to, producing, or using rays like light but lying outside the visible spectrum at its red end

infrared radiation

infrared noun

Medical Definition

infrared

1 of 2 adjective

in·​fra·​red ˌin-frə-ˈred 

1

: lying outside the visible spectrum at its red end

—used of radiation having a wavelength between about 700 nanometers and 1 millimeter

2

: relating to, producing, or employing infrared radiation

infrared therapy

infrared

2 of 2 noun

: infrared radiation