Rail

n. 1 level or sloping bar or series of bars: a used to hang things on. b as the top of banisters. c forming part of a fence or barrier as protection. 2 steel bar or continuous line of bars laid on the ground, usu. as a railway. 3 (often attrib.) railway. v. 1 furnish with a rail or rails. 2 (usu. foil. by in. oft) enclose with rails. o off the rails disorgataked; out of order; deranged. [French reille from Latin regula RULE]