infrared radiation

1. Invisible radiation in the part of the electromagnetic spectrum characterized by wavelengths just longer than those of ordinary visible red light and shorter than those of microwaves or radio waves . ( Compare ultraviolet radiation .)

Notes

The heat we feel from a glowing coal or an incandescent light bulb is from infrared rays.

Example Sentences

Remote-sensing instruments in Earth-orbit satellites measure radar, visible light, and infrared radiation.

From Project Gutenberg