<p><strong>Noun</strong></p><ul><li>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 nanometers to 1 millimeter.</li><li>An influx: a rushing in.</li><li>The place at which one stream flows into another or into the sea; the mouth of a stream.</li></ul><p><strong>Adjective</strong></p><ul><li>Noting or pertaining to the infrared or its component rays: infrared radiation.</li></ul>