An optical system of close equidistant and parallel lines or bars, especially lines ruled on a polished surface, used for producing spectra by diffraction.
The strong wooden lattice used to cover a hatch, admitting light and air; also, a movable lattice used for the flooring of boats.
A barrier that has parallel or crossed bars blocking a passage but admitting air.
A frame of iron bars to hold a fire.
The sound made by something that grates against something else.
The loose material that comes from something being grated.
Harsh and unpleasant.
Abrasive; tending to annoy.
Characteristic of a symphony