GRATING

adj. and n. Grat'i'n". Lat., radens (1st def.), crepitus (2d def.). Fr., rude (adj.), rude e 'n., 2d def.). Ger., knirschend (adj.), Knirschen (2d def.), Gitterwerk (3d def.). 1. (Adj.) of sounds, harsh, as when two hard, rough objects are moved upon each other. 2. (N.) a sound of that sort. 3. (N.) a latticework; in optics, a gla minutely furrowed with fine parallel rulings, acting to produce dispersion of chromatic rays. [s. 237]