Main entry: diffraction grating, grating
Definition: optical device consisting of a surface with many parallel grooves in it; disperses a beam of light (or other electromagnetic radiation) into its wavelengths to produce its spectrum
Definition: a frame of iron bars to hold a fire
Definition: a barrier that has parallel or crossed bars blocking a passage but admitting air
Main entry: grating, gravelly, rough, scratchy, rasping, raspy
Definition: unpleasantly harsh or grating in sound
Usage: a gravelly voice