infrared

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

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

See infrared defined for kids

Recent Examples of infrared from the Web

Their cameras are variously customized to detect light beyond the visible spectrum (night vision) or heat signatures (thermal infrared), and are either carried either by hand or mounted on tiny drones.

— patrick blanchfield, Esquire, "Shot in the Dark," 1 Aug. 2017
Who would say no to a seriously panoramic sky lounge roof ($900 extra) and multicolored mood lighting adjustable at the level of an infrared sauna?

— hannah elliott, Bloomberg.com, "Here's a Superpowerful BMW That's Best Enjoyed From the Back Seat," 31 July 2017
Birmingham Fire and Rescue even searched the murky water using infrared technology, but nothing was found in the pool.

— carol robinson, AL.com, "Toddler's death in family's pool during parents' wedding reception ruled accidental," 25 July 2017
So, the Star bought an infrared thermometer to measure the external temperature of some things everyone needs to be careful around while in the summer heat.

— lily o’neill, kansascity, "How hot is that surface? We measured pavement, steering wheels, slides and more," 21 July 2017
Some time later, the Bosch group — readying a 500-year-anniversary exhibit in the artist’s hometown of Den Bosch, Netherlands — requested high-resolution and infrared images of the painting.

— david frese, kansascity.com, "Rare Bosch painting, just one of five in U.S., finally on display at the Nelson," 28 June 2017
Hilton Lewis Hilton Lewis is director of the W. M. Keck Observatory on the Island of Hawaii, home to the world's two largest optical/infrared telescopes.

— hilton lewis, Scientific American Blog Network, "In Memoriam: Jerry Nelson, Legendary Telescope Designer," 16 June 2017
Hilton Lewis Hilton Lewis is director of the W. M. Keck Observatory on the Island of Hawaii, home to the world's two largest optical/infrared telescopes.

— hilton lewis, Scientific American Blog Network, "In Memoriam: Jerry Nelson, Legendary Telescope Designer," 16 June 2017
As Liam walks along a black strip of plastic affixed to the floor, a series of eight infrared cameras connected to a computer near the back of the room track the movement of the markers.

— nicholette zeliadt, Scientific American, "Autism in Motion: Could Motor Problems Trigger Social Ones?," 5 June 2017

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

INFRARED Defined for English Language Learners

infrared

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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

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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

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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

Learn More about infrared

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

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infrared

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infrared

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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

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