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

The sprawling 5,000-square-foot facility includes treatment rooms, a sauna, flotation therapy, and an infrared sauna. —Ryan Smith, Travel + Leisure, 20 June 2024

An infrared sauna at RoseBar, which features biohacking and meditation Six Senses Also at Six Senses in Ibiza is restaurant The Beach Caves Six Senses Hotels and wellness resorts are jumping on the trend too, some offering advanced medical treatments, such as IV therapy and genetic testing. —Mary Holland, Condé Nast Traveler, 18 June 2024

The satellites have infrared sensors that can track heat loss, which ultimately indicates how much ice has melted and is lost to the ocean. —Riis Williams, Scientific American, 7 June 2024

Although humans can't see it, artist Scott Kildall uses an infrared sensor to translate near-infrared light into sound. —Suzanne Nuyen, NPR, 4 June 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