1 Place for the transaction of private or public business, e.g. room or department in which the paperwork of an establishment is dealt with.
2 Building or set of rooms in which the business of a department of Government is carried out, e.g. Foreign Office, Home Office, etc.
3 Privy (i.e. House of Office).
4 Authorized form of ecclesiastical service, i.e. Divine Office, Mass, or Holy Communion.
5 Ecclesiastical tribunal for suppression of heresy (Holy Office, otherwise known as the Inquisition). 6. In the plural, those parts of a house, or buildings attached to it, used for the kitchens, pantry, laundry, scullery, etc., sometimes including stables, barns, out-houses, etc.