Ray

ray out/forth (v.)
(of light, thought, emotion, etc.)
放射

raze (v.) to the ground
(also rase) 夷平

Rayleigh scattering
It accounts, for example, for the blue colour of the sky, since blue light is scattered more efficiently than red.

razor-edge
found themselves on a razor-edge
(or razor's edge)

(from OERD 1995)