As a noun, a proprietor or owner; one who has the exclusive title to a thing; one who possesses or holds the title to a thing in his or her own right; one who possesses the dominion or ownership of a thing in his or her own right.
As an adjective, belonging to ownership; owned by a particular person; belonging or pertaining to a proprietor; relating to a certain owner or proprietor.
Proprietary refers to ownership or characteristics relating to ownership. It describes all the rights that the owner of property can exercise. Proprietary articles are items that are manufactured and marketed under an exclusive right.
Municipal corporations have a proprietary function, a term describing the duty or capacity of a city to enter into business ventures or to perform discretionary acts in the best interests of the citizens. Proprietary functions differ from governmental functions, which are duties that a city performs as a political subdivision of a state.