1. A thin piece of anything, especially of marble or other stone, having plane surfaces.
2. An outside piece taken from a log or timber in sawing it into boards, planks, etc.
3. (Science: zoology) The wry neck.
4. The slack part of a sail. Slab line, a line or small rope by which seamen haul up the foot of the mainsail or foresail.
Origin: OE. Slabbe, of uncertain origin; perhaps originally meaning, a smooth piece, and akin to slape, Icel. Sleipr slippery, and E. Slip, v. I.