| the longer wavelengths of electromagnetic radiation in the infrared region of the spectrum, beyond the red end of the visible spectrum, from 50 to 1000 micrometers. Abbreviation: FIR |
.| far-in·fra·red radiation (fär'ĭn'frə-rěd') n. See far-red radiation. |
| far-red radiation (fär'rěd') n. Electromagnetic radiation having the longest wavelengths in the infrared region, between approximately 50 and 1,000 micrometers. Also called far-infrared radiation. |
far-infrared radiation  (fär'ĭn'frə-rěd') Pronunciation Key
Infrared electromagnetic radiation of very long wavelengths, in the range of 2-50 microns. It is used in medicine to provide a penetrating heat to the body. Also called far-red radiation. |
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