Counter-sunk
Shipbuilding
The hollows in iron plates, etc., which are excavated by an instrument called a counter-sunk bitt to receive the heads of screws or nails so that they may be flush or even with the surface.
The hollows in iron plates, etc., which are excavated by an instrument called a counter-sunk bitt to receive the heads of screws or nails so that they may be flush or even with the surface.