gypsum plank[′jip·səm ¦plaŋk]
A structural precast unit consisting of gypsum core reinforced with welded galvanized steel mesh and bounded on all four edges with a tongue-and-groove steel form; used as the roof deck of steel-frame buildings, and sometimes for the floor system.
1. British term for gypsum lath.
2. A lightweight, fire-resistant, structural pre-cast roof deck having a gypsum core reinforced with galvanized-steel mesh.