An Etymological Dictionary of Astronomy and Astrophysics

A broad, flat, somewhat thick piece of stone, wood, or other solid material (Dictionary.com).

Etymology (EN): M.E sclabbe, slabbe of unknown origin, maybe related to O.Fr. escopel, escalpe “thin fragment of wood.”

Etymology (PE): Tiyât, from Kurd. (Ilâm) teyat “slab.”