BALK n.
to deliver the ball. Balk line (Billiards), a line across a billiard table near one end, marking a limit within which the cue balls are placed in beginning a game; also, a line around the table, parallel to the sides, used in playing a particular game, called the balk line game.
BAY n.
compartment of the walls, roof, or other part of a building, or of the whole building, as marked off by the buttresses, vaulting, mullions of a window, etc.; one of the main divisions of any structure, as the part of a bridge between two piers.