Noah Webster's New International Dictionary of the English Language
1. (a.) Emitting or proceeding as from a center; resembling rays; radiating; radiate.
2. (a.) Especially, emitting or darting rays of light or heat; issuing in beams or rays; beaming with brightness; emitting a vivid light or splendor; as, the radiant sun.
3. (a.) Beaming with vivacity and happiness; as, a radiant face.
4. (a.) Giving off rays; -- said of a bearing; as, the sun radiant; a crown radiant.
5. (a.) Having a ray like appearance, as the large marginal flowers of certain umbelliferous plants; -- said also of the cluster which has such marginal flowers.
6. (n.) The luminous point or object from which light emanates; also, a body radiating light brightly.
7. (n.) A straight line proceeding from a given point, or fixed pole, about which it is conceived to revolve.
8. (n.) The point in the heavens at which the apparent paths of shooting stars meet, when traced backward, or whence they appear to radiate.