Underwater vessel powered by nuclear reactor.

Underwater cables transmitting data globally.

A submarine base is a military base that shelters submarines and their personnel.

"Yellow Submarine" is a song by the English rock band the Beatles from their 1966 album Revolver.

A submarine canyon is a steep-sided valley cut into the seabed of the continental slope, sometimes extending well onto the continental shelf, having nearly vertical walls, and occasionally having canyon wall heights of up to , from canyon floor to canyon rim, as with the Great Bahama Canyon.

Submarine designed for combat operations.

(geology) A shallow marine sediment beyond the opening of a large river etc.

A midget submarine is any submarine under 150 tons, typically operated by a crew of one or two but sometimes up to six or nine, with little or no on-board living accommodation.

Underwater vessel powered by nuclear reactor.