pontoon

A floating structure, such as a flatbottom boat, used to support a bridge.

A floating structure serving as a dock.

Either of two floating structures attached to a seaplane.

Same as catamaran, 4.

In milit engin., a flat-bottomed boat, or any light framework or floating structure, used in the construction of a temporary bridge over a river.

Nautical, a lighter; a low flat vessel resembling a barge, furnished with cranes, capstans, and other machinery, used in careening ships, chiefly in the Mediterranean.

In hydraulic engineering: A water-tight structure or frame placed beneath a submerged vessel and then filled with air to assist in refloating the vessel.

A water-tight structure which is sunk by filling with water and raised by pumping it out, used to close a sluiceway or entrance to a dock. Also spelled ponton.

In anatomy, a loop or knuckle of the small intestine: so called from the way it appears to float in the abdominal cavity. See the quotation under mesentery.

In brewing, one of the cleansing-rounds or cleansing-squares used for clarifying ale.