luminary (n.) Look up luminary at Dictionary.com
mid-15c., "lamp, light-giver, source of light," from Old French luminarie (12c.), "lamp, lights, lighting; candles; brightness, illumination," from Late Latin luminare "light, torch, lamp, heavenly body," literally "that which gives light," from Latin lumen (genitive luminis) "light, source of light, daylight, the light of the eye; distinguished person, ornament, glory," related to lucere "to shine," from suffixed (iterative) form of PIE root *leuk- "light, brightness."

From late 15c. as "celestial body." Sense of "notable person" is first recorded 1690s, though the Middle English word also had a figurative sense of "source of spiritual light, example of holiness" (mid-15c.). As an adjective, "pertaining to light," from 1794 but this is rare.