ETYM Latin radians, -antis, p. pr. of radiare to emit rays or beams, from radius ray: cf. French radiant. Related to Radius, Ray a divergent line.
1. Emitting or proceeding as from a center; rays; radiating; radiate.
2. Especially, emitting or darting rays of light or heat; issuing in beams or rays; beaming with brightness; emitting a vivid light or splendor.
3. Beaming with vivacity and happiness.
4. Having a raylike appearance, as the large marginal flowers of certain umbelliferous plants; -- said also of the cluster which has such marginal flowers.
Something that radiates: as a point in the heavens at which the visible paths of meteors appear to meet when traced backward; the part of a gas or electric heater that becomes incandescent