What is another word for "slab"?

Roget's Thesaurus (1911) lists these synonyms for "slab": arm, armlet, artesian, bay, bayou, bed, belt, bight, board, broad, coat, continental, course, cove, cover, covered, covering, creek, cut, dam, dead, dess, dike, discoid, ditch, dyke, escarpment, eschar, estuary, even, film, fiord, firth, fish, flag, flagstone, flake, flat, flatness, flatten.