What is another word for "ceiling"?

Roget's Thesaurus (1911) lists these synonyms for "ceiling": arc, arcade, arch, arched, arcuation, bay, bend, bending, bough, bought, bow, cardioid, carve, catenary, caustic, concameration, conchoid, crane, crescent, crook, curl, curling, curvation, curvature, curve, curvity, deflection, deflexion, detour, devexity, deviation, festoon, flection, flexion, flexure, function, half-moon, helix, hook, horseshoe.