sections cut out of the gunnels to allow seawater to drain off the decks back into the ocean
Gravity fed drain in a boat to allow water to drain out and overboard.
Holes or gutters round the edge of the ship's deck to let water run off.
Drains from decks to carry off accumulations of rainwater, condensation or seawater. Scuppers are located in the gutters or waterways, on open decks, and connect to pipes usually leading overboard.
Holes in the side of the ship at the same level as the deck to allow water to drain out.