1. A type of drilled or augured piling. 2. A cylindrical, sitecast concrete foundation that penetrates through unsatisfactory soil to rest upon an underlying stratum of rock or satisfactory soil. 3. A foundation pier, either circular or rectilinear in plan, usually sunk to rock either by means of gravity, compressed air or by the open-well method. 4. A panel sunk below the normal surface in flat or vaulted ceilings.