Nouns

(n)grate, gratinga barrier that has parallel or crossed bars blocking a passage but admitting air
(n)grate, gratinga frame of iron bars to hold a fire
(n)diffraction grating, gratingoptical 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

Adjectives

(s)grating, gravelly, rasping, raspy, rough, scratchyunpleasantly harsh or grating in sound“a gravelly voice”