(systems theory) An underlying base or foundation especially for an organization or system. / The basic facilities, services and installations needed for the functioning of a community or society.

(taxonomy) A zoological classification sometimes inserted below subclass and above subterclass (rarely used) and superorder.

(law) A minor offence, petty crime. / A violation; breach. / (ice hockey) A major violation of rules which leads to a penalty, if detected by the referee.

(uncountable) The electromagnetic radiation of a wavelength longer than visible light, but shorter than microwave radiation, having a wavelength between 700 nm and 1 mm.

Having a wavelength in the infrared spectrum.

(American football) an infraction in which a football player, on defense, gets into or crosses the neutral zone during the snap, causing an offensive player to false start. The penalty is against the defense, not the offense. It is a 5 yard penalty.

(physics) Electromagnetic radiation having a wavelength approximately between 1 micrometre and 1 millimetre; perceived as heat.

(physics) infrared light closest in wavelength to visible light, from .7 - 1.4 µm.

(analytical chemistry) The spectroscopic study of the interaction of matter with infrared radiation; used as an analytical tool to identify (mostly organic) compounds.

An incandescent lamp designed to produce radiant thermal energy in the infrared part of the electromagnetic spectrum.