infrared

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

|Updated on: 12 Aug 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

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Recent Examples of infrared from the Web

That yields strong heat-resistant rolls that are sliced thin to be used as coverings or windows protecting infrared targeting systems and other sensors on military equipment.

— paul brinkmann, OrlandoSentinel.com, "Vibration from Orlando City Stadium construction damaged high-tech business next door, lawsuit says," 31 May 2018
In order to take pictures in infrared, the ABI needs to be at approximately -350℉. This is very cold, and in order to reach such a low temperature the ABI needs a functioning cooling system.

— avery thompson, Popular Mechanics, "NOAA's New Weather Satellite Has a Cooling Problem," 25 May 2018
Using a 26-foot Gemini North telescope, the team of scientists studied the reflected sunlight in infrared and determined what types of molecules made up the planet's atmosphere, the release said.

— the washington post, NOLA.com, "Planet Uranus smells of flatulence, rotten eggs, scientists say," 24 Apr. 2018
But because the wavelength of near-infrared light is smaller than a micron, smaller than the smallest neuron, Jepsen believes the resolution of the technology is fine enough to make thoughts visible too.

— jason pontin, WIRED, "Thought-Reading Machines and the Death of Love," 16 Apr. 2018
The helicopter then began filming the man in infrared.

— ryan lillis and anita chabria, sacbee, "Sacramento police chief believes black man killed by cops was alleged burglar from 911 call | The Sacramento Bee," 22 Mar. 2018
Iris scanning involves digitally mapping out the intricate and uniquely woven designs of people’s irises by illuminating them with near-infrared light.

— david muller, Car and Driver, "Gentex Wants to Bring Iris Scanning to Your Car," 12 Jan. 2018
On | Off Using infrared cameras, recorders, spirit boxes, and glow-in-the-dark buttons, the RIP squad camped out in Russell's space for six hours on January 29th in an attempt to find paranormal energy.

— devin alessio, ELLE Decor, "Ghosts Saved This Building From Being Destroyed," 15 Mar. 2016
Where: Weightless, 600 Distillery Commons, Suite 150, Louisville; Acqua Wellness, 10517A Fischer Park Drive, Louisville What: Uses infrared light to penetrate human tissue and stimulate fat cells.

— zahria rogers, The Courier-Journal, "Concierge IV hydration therapy service seeks to rehydrate Louisville," 12 July 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.