Pronunciation: (in"fru-red'), [key]
the part of the invisible spectrum that is contiguous to the red end of the visible spectrum and that comprises electromagnetic radiation of wavelengths from 800 nm to 1 mm.
noting or pertaining to the infrared or its component rays: infrared radiation. Cf. ultraviolet. Also,in"fra-red'.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.