Definition of "battleship"

(military, nautical) A large capital warship displacing thousands to tens of thousands of tons, heavily armoured and armed with large-caliber guns; now obsolescent and replaced by smaller vessels with guided missiles.

1. (science fiction, by extension) A starship of comparable role  examples

(military, nautical, archaic) A ship of the line.

A non-functional rocket stage, used for configuration and integration tests.  examples

A guessing game played on grid paper; see Battleship (game).  examples