submarine, n.Definitions

The Submarine is a big metal bubble with a motor

A Submarine is the only ship that can travel overseas underseas.

A Submarine is a boat that sink on purpose

A Submarine is a prison with a chance of drowning

A Submarine is a plane that flies in a different medium.

A Submarine is a robotic blue whale.

A Submarine is a boat that's able to hold its breath for a long time

A Submarine is a reverse fish tank with the humans and air on the inside and the fishes and water on the outside.