| Submarine 1. (a.) Being, acting, or growing, under water in the sea; as, submarine navigators; submarine plants. 2. (n.) A submarine plant or animal. Thesaurus Entries Aqua-Lung, U-boat, U-boot, Unterseeboot, air cylinder, aquascope, bathyscaphe, bathysphere, benthoscope, buried, diving bell, diving boat, diving chamber, diving goggles, diving helmet, diving hood, diving mask, diving suit, drowned, engulfed, flooded, immersed, inundated, periscope, pigboat, scuba, snorkel, sub, subaqueous, submerged, submersed, submersible, sunken, swim fins, undersea, underwater, wet suit |