infrared

adjective in·fra·red \ ˌin-frə-ˈred , -(ˌ)frä- , -fə- \

|Updated on: 17 Jun 2018

Definition of infrared

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

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infrared

noun

See infrared defined for English-language learners

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Recent Examples of infrared from the Web

Compal made a convertible notebook with a 15.6-inch 4K touch display, an infrared camera, a fingerprint sensor, 13 hours of battery life, a stylus, four digital microphones, and two speakers.

— shannon liao, The Verge, "Amazon’s new all-in-one and laptop designs could get Alexa into even more PCs," 5 June 2018
Rescue crews have used infrared cameras and dogs to search for the teens.

— travis fedschun, Fox News, "Georgia teenagers missing after being swept away in swollen creek," 3 June 2018
Antennas can be tested for weakness to jamming, details of the engines could help detect it with infrared, and onboard navigation data can be used to inform the placement of defensive radar.

— joe pappalardo, Popular Mechanics, "What Happens to a Cruise Missile Captured by the Russians," 26 Apr. 2018
According to the patent, the drone’s communication system would include an array of sensors, including a depth sensor and cameras to detect visible, infrared and ultraviolet light.

— hamza shaban, chicagotribune.com, "Amazon patents delivery drones that can react to people screaming and flailing," 23 Mar. 2018
Make sure the glazing helps reduce ultraviolet and infrared rays.

— steven sclaroff, New York Times, "Advice for Renovating Your Home," 7 Mar. 2018
Think swords into plowshares, but in AdaSky's case, the sword is the far infrared and the plowshare is called Viper.

— jonathan m. gitlin, Ars Technica, "The car of the future is taking shape—and it will know how we feel about it," 11 Feb. 2018
Composed of red algae and hydrating meadowfoam seed oil, Unseen protects against UVA and UVB rays, as well infrared and blue light emitted by electronic devices, like smartphones and laptops.

— shammara lawrence, Allure, "Supergoop's Unseen Sunscreen Is "Invisible" on Every Skin Tone," 8 Jan. 2018
About 40 golf courses in the United States and Canada already are customers of another Boston startup, GreenSight Agronomics, which leases small airborne drones outfitted with infrared cameras.

— scott kirsner, BostonGlobe.com, "How golf startups are bringing innovation to a tradition-steeped game," 25 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'infrared.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of infrared

1881

in the meaning defined at sense 1

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INFRARED Defined for English Language Learners

infrared

adjective

Definition of infrared for English Language Learners

: producing or using rays of light that cannot be seen and that are longer than rays that produce red light

INFRARED Defined for Kids

infrared

adjective in·fra·red \ ˌin-frə-ˈred \

Definition of infrared for Students

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

Medical Dictionary

infrared

adjective in·fra·red \ ˌin-frə-ˈred \

medical Definition of infrared

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

noun

medical Definition of infrared

: infrared radiation

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See words that rhyme with infrared Spanish Central: Translation of infrared Nglish: Translation of infrared for Spanish speakers

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infrared

Definition of infrared

infrared

Recent Examples of infrared from the Web

First Known Use of infrared

INFRARED Defined for English Language Learners

infrared

Definition of infrared for English Language Learners

INFRARED Defined for Kids

infrared

Definition of infrared for Students

Medical Dictionary

infrared

medical Definition of infrared

infrared

medical Definition of infrared

Learn More about infrared

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