The useful horsepower of an engine as measured at its drive shaft.

Alternative form of horse racing

(gambling) A person who bets on horse races.

plural of horsebox

plural of horseburger

A burger made from horsemeat.

plural of horseshoe map

(mathematics) Any of a class of chaotic maps of the square into itself, used in the study of dynamical systems.

(rail transport) A streetcar or tram drawn by a horse.

plural of horsecar