A narrow beam of light, which emanate from a single bright source that proceed in one direction.
See Alexandrite Tsarstone collectors guide, Definition of Ray, http://w.alexandrite.com/viewpage.html?id=GG-103-00003 (A narrow beam of light, which emanate from a single bright source that proceed in one direction.) (as of Jun. 01, 2026, 04:49 GMT).