Radiation is the process of emitting energy in the form of waves or particles. The crossword solutions for the term radiation include EMISSION (8 letters), DIFFUSION (9 letters), RAY (3 letters), LIGHT (5 letters), BEAM (4 letters), and gamma (5 letters). EMISSION is the process of releasing energy from a source, while DIFFUSION is the spreading of something more widely. A RAY is a line of LIGHT that travels in a straight line, while LIGHT is electromagnetic radiation that is visible to the human eye. A BEAM is a concentrated RAY of LIGHT or other type of radiation, and gamma radiation is a type of electromagnetic radiation that is emitted from the nucleus of an atom.