(grāt) v. grat·ed, grat·ing, v.t.
1. To reduce to small particles by rubbing with a rough surface or through a grate.
2. To rub or grind so as to produce a harsh, scraping sound.
3. To annoy; irritate: to grate the nerves.
4. Archaic To wear or scrape away.
—v.i.
5. To sound harshly, from or as from scraping or grinding; creak.
6. To have an irritating effect: with on or upon.
—noun A harsh, grinding noise. ♦ Homophone: great. [<OF grater <Gmc.]

(grāt) noun
1. A framework of bars, as to close an opening, or to hold fuel in burning.
2. A perforated metallic plate through which the ores pass after being crushed under stamps.
3. A fireplace.
4. Obs. A cage furnished with grates; a place of confinement.
—v.t. grat·ed, grat·ing To fit with a grate or grates. ♦ Homophone: great. [<Med. L grata <Ital. <L cratis a lattice]