intransitive. To become submerged in water; to go under or to the bottom of the sea, a lake, etc.; (of a ship) to founder. Also in figurative context.

intransitive with reflexive meaning. To drown, or be drowned; (of a ship) to go down, sink. Cf. adrink, v.

intransitive. Of a ship: to founder, to sink; to be shipwrecked.

intransitive. Of a vessel: To fill with water and sink, go to the bottom.

The ground or bed under the water of a lake, sea, or river. to go to the bottom and variants: to sink, founder; to be wrecked. Cf. river bottom, n.…