(nautical) Someone charged with looking after buoys. / A ship used to maintain navigational buoys.

plural of life-buoy

(nautical) An empty cask employed to buoy up the cable in rocky anchorage.

(Britain) A buoyant object (most commonly torus-shaped) that is used as a life-saving device by keeping a person afloat. / (Britain, metaphoric) Something that rescues one from difficulties.

To let the anchor buoy fall by the ship's side into the water, before letting go the anchor.

A buoy fitted with a whistle that is blown by the action of the waves.

plural of dan buoy

(nautical) a buoy at which a boat or ship can moor (tie up), usually in a harbour, but also in coastal waters for large ships.

plural of light buoy

(nautical) A buoy with a light on top which is lit at night to aid navigation.