Grating /(?)/

Grat·ing

Grating

n.
  1. A partition, covering, or frame of parallel or cross bars; a latticework resembling a window grate; as, the grating of a prison or convent.
  2. A system of close equidistant parallel lines or bars, esp. lines ruled on a polished surface, used for producing spectra by diffraction; -- called also diffraction grating. (Optics)
  3. The strong wooden lattice used to cover a hatch, admitting light and air; also, a movable Lattice used for the flooring of boats. (Naut.)

Grating

a.
  1. That grates; making a harsh sound; harsh.

Grating

n.
  1. A harsh sound caused by attrition.