A lot vs. Alot: 9 Grammatical Pitfalls
mid-14c., "chief residence of a lord," from Old French mansion "stay, permanent abode, house, habitation, home; mansion; state, situation" (13c.), from Latin mansionem (nominative mansio) "a staying, a remaining, night quarters, station," noun of action from past participle stem of manere "to stay, abide," from PIE *men- "to remain, wait for" (cf. Greek menein "to remain," Persian mandan "to remain"). Sense of "any large and stately house" is from 1510s. The word also was used in Middle English as "a stop or stage of a journey," hence probably astrological sense "temporary home" (late 14c.).
scenic device used in medieval theatrical staging. Individual mansions represented different locales in biblical stories and in scenes from the life of Christ as performed in churches. A mansion consisted of a small booth containing a stage with corner posts supporting a canopy and decorated curtains and often a chair and props to be used by the actors in that scene. Mansions were usually arranged elliptically in the nave of the church. Appropriate architectural features of the church were also used as mansions: the crypt served as the tomb of Christ or as hell and the choir loft was frequently used as heaven.