BASEMENT n.
The outer wall of the ground story of a building, or of a part of that story, when treated as a distinct substructure. ( See Base, n., 3 (a).) Hence: The rooms of a ground floor, collectively. Basement membrane (Anat.), a delicate membrane composed of a single layer of flat cells, forming the substratum upon which, in…
BAY n.
A principal compartment of the walls, roof, or other part of a building, or of the whole building, as marked off by the buttresses, vaulting, mullions of a window, etc.; one of the main divisions of any structure, as the part of a bridge between two piers.