DOLPHIN, noun [Gr.]
1. A genus of cetaceous fish, with teeth in both jaws, and a pipe in the head, comprehending the dolphin the porpoise, the grampus and the beluga. But the fish to which seamen give this name, is the Coryphaena hippuris of Linne. It has a flat roundish snout and a tapering body, with a fin running along the back from the head to the tail, consisting of a coriaceous membrane with soft spines.
2. In ancient Greece, a machine suspended over the sea, to be dropped on any vessel passing under it.