Submarine

Part of speech: noun (n.)

A submarine plant or animal.

Part of speech: adjective (a.)

Being, acting, or growing, under water in the sea; as, submarine navigators; submarine plants. Submarine armor, a waterproof dress of strong material, having a helmet into which air for breathing is pumped through a tube leading from above the surface to enable a diver to remain under water. -- Submarine cable. See Telegraph cable, under Telegraph. -- Submarine mine. See Torpedo, 2 (a).