n. A common cyprinoid fish of Europe, Leuciscus rutilus.n. In the United States, one of many different fishes like or mistaken for the roach, as some sunfish of the genus Lepomis or Pomotis;n. the spot or lafayetten. the American chub, Semotilus atromaculatus.n. A rock.n. Refuse gritty stone.To make hard like a rock.n. Nautical, a concave curve in the leech or foot of a square sail, to improve the fit of the sail.n. An upstanding curl or roll of hair over the forehead, like the roach of a sail.To cause to stand up or arch; make projecting or convex: as, his hair was roached up over his forehead.To cut short so as to cause to stand up straight; hog: said of horses' manes.n. A rash, or eruption on the skin.n. A cockroach.n. The redfin, Rutilus rutilus, a common European shiner or minnow of the family Cyprinidæ.n. In England, a shell limestone occurring at the top of the Portland Stone or Portlandian on the Isle of Portland.