奥(ao4) denotes a place inside a house,where offerings to one's ancestors are put. It is located in the south western corner of the house.
Beside this term, are there further words like this?
四隅（four corners of a room）
宧（yí ／ ㄧˊ）：室內東北角（northeastern corner）
窔（yào ／ ㄧㄠˋ ）同“穾”：室內東南角（southeast corner）
奥（ào ／ ㄠˋ）：室內西南角（southwest corner）
屋漏（wū lòu ／ ㄨ ㄌㄡˋ）：室內西北角（northwest corner）