<p><strong>Noun</strong></p><ul><li>a vessel that can be submerged and navigated under water, usually built for warfare and armed with torpedoes or guided missiles</li><li>something situated or living under the surface of the sea, as a plant or animal</li><li>Chiefly Northeastern and North Midland U.S. a hero sandwich</li></ul><p><strong>Adjective</strong></p><ul><li>situated, occurring, operating, or living under the surface of the sea: a submarine mountain</li><li>of, relating to, or carried on by a submarine or submarines: submarine warfare</li></ul><p><strong>Verb (used without object)</strong></p><ul><li>to participate in the operating of a submarine</li><li>to move or slide under something</li><li>Slang. to be thrown under the steering wheel of the vehicle one is driving during a frontal crash</li><li>to be thrown out of one's seat belt in such a crash</li></ul><p><strong>Verb (used with object)</strong></p><ul><li>to attack or sink by submarine</li></ul>