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
Cindy Crawford, Julianne Hough and Halle Berry are among the celebrities who are turning up the heat in their wellness routines amid the rising trend of infrared and traditional sauna use.
—
Ashley Hume, FOXNews.com, 1 Jan. 2026
The optical reflector selectively redirects invisible near-infrared light toward the solar cells while allowing most visible light to pass through.
—Georgina Jedikovska, Interesting Engineering, 30 Dec. 2025
Whether you’re drawn to the serenity of a spa-like bathroom, a quiet meditation corner, or a wellness-enhancing feature like an infrared sauna or cold plunge tub, the goal is the same—to design with intention and foster reconnection.
—Colleen Sullivan, Better Homes & Gardens, 27 Dec. 2025
Because of its short wavelength, infrared laser light must be lined up very precisely with the core of an optical fiber, which is only around 10 µm across.
—IEEE Spectrum, 27 Dec. 2025
See All Example Sentences for infrared
Examples are automatically compiled from online sources to
show current usage.
Read More
Opinions expressed in the examples do not represent those of Merriam-Webster or its editors.
Send us feedback.
Ashley Hume, FOXNews.com, 1 Jan. 2026
The optical reflector selectively redirects invisible near-infrared light toward the solar cells while allowing most visible light to pass through.
—Georgina Jedikovska, Interesting Engineering, 30 Dec. 2025
Whether you’re drawn to the serenity of a spa-like bathroom, a quiet meditation corner, or a wellness-enhancing feature like an infrared sauna or cold plunge tub, the goal is the same—to design with intention and foster reconnection.
—Colleen Sullivan, Better Homes & Gardens, 27 Dec. 2025
Because of its short wavelength, infrared laser light must be lined up very precisely with the core of an optical fiber, which is only around 10 µm across.
—IEEE Spectrum, 27 Dec. 2025
See All Example Sentences for infrared
Cite this Entry
“Infrared.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/infrared. Accessed 2 Jan. 2026.
Copy CitationKids 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
Love words? Need even more definitions?
Merriam-Webster unabridged
Share