chaulk / chock [tʃeist]
chaulk – n. – limestone, dolomite
chock – n. – 1. a block or wedge of wood used to prevent a wheel, etc., from moving; 2. a strong metal eye or hook on a ship’s deck through which a line may be passed or secured; v. tr. – 1. fit or make fast with chocks; 2. (Brit.) cram full; adv. – as closely or tightly as possible