Definitions
1.AdjectiveBeing, relating to, or made for use underwater, especially beneath the sea.
2.AdjectiveHidden or undisclosed."a submarine patent"
3.AdjectiveOf a pitch, thrown with the hand lower than the elbow.
4.NounA boat that can go underwater.
5.NounAlternative form of submarine sandwich.
6.NounA pitch delivered with an underhand motion.
7.NounAny submarine plant or animal.
8.NounA stowaway on a seagoing vessel.
9.VerbTo operate or serve on a submarine.
10.VerbTo torpedo; to destroy with a sudden sneak attack.
11.VerbTo sink or submerge oneself.
12.VerbTo slide forwards underneath one's seat belt (during a crash or sudden stop)."The seatback should always be up while driving so that the occupant doesn't submarine and potentially suffer severe internal injury."