views updated May 23 2018

in·fra·red / ˌinfrəˈred/ • adj. (of electromagnetic radiation) having a wavelength just greater than that of the red end of the visible light spectrum but less than that of microwaves. Infrared radiation has a wavelength from about 800 nm to 1 mm, and is emitted particularly by heated objects. ∎  (of equipment or techniques) using or concerned with this radiation: infrared cameras.• n. the infrared region of the spectrum; infrared radiation.