Tending to strike unexpectedly, in the fashion of one who submarines

(dated) The use of submarines in warfare.

(hydrology, oceanology) A river-like current on the seabed.

A sandwich made on a long roll split lengthwise.

(informal) A patent first published and granted long after the filing of the initial application.

plural of submarine river

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

(baseball) A pitch thrown with an underarm-to-sidearm motion.

(military) Intended to attack submarines.

plural of submarine chaser