noun

1. 1. any of the thin lines, or beams, of light that appear to come from a bright source
   2. a graphic representation of one of these, as in heraldry
2. 1. any of several lines radiating from a center; radius
   2. any straight line that extends from a point
3. a disclosure of mental or spiritual enlightenment a ray of intelligence
4. a tiny amount; slight trace a ray of hope
5. Bot.
   1. ray flower
   2. any of the pedicels, or flower stalks, of an umbel
   3. a medullary ray
6. Physics
   1. a stream of particles given off by a radioactive substance
   2. any of the particles in such a stream
   3. a straight line along which any part of a wave of radiant energy is regarded as traveling from its source to any given point
   4. a beam of radiant energy of very small diameter
7. Zool.
   1. any of the bony spines supporting the fin membrane of a fish
   2. any of the sectors of a radially symmetrical animal, as a starfish

Etymology: OFr rai < L radius: see radius

intransitive verb

1. to shine forth in rays
2. to radiate

transitive verb

1. to send out in rays; emit
2. to supply with rays or radiating lines