submarine, n.All

A Submarine is a robotic blue whale.

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

A Submarine is a boat that sink on purpose

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

Pepsi was once the 6th largest military power in the world for a short time when the Soviet Union traded the company 17 submarines, a cruiser, a frigate, and a destroyer for Pepsi to be sold in the Soviet Union

The Submarine is a big metal bubble with a motor

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

Armadillos can walk underwater

Hippopotamuses are born under water

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

A Submarine is a prison with a chance of drowning