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noun pro·pri·e·tary \prə-ˈprī-ə-ˌter-ē\

Definition of proprietary

plural pro·pri·e·tar·ies

  1. 1 :  one that possesses, owns, or holds exclusive right to something; specifically :  proprietor 1

  2. 2 :  something that is used, produced, or marketed under exclusive legal right of the inventor or maker; specifically :  a drug (as a patent medicine) that is protected by secrecy, patent, or copyright against free competition as to name, product, composition, or process of manufacture

  3. 3 :  a business secretly owned by and run as a cover for an intelligence organization

Origin of proprietary

Middle English propietarie, from Anglo-French, from Medieval Latin propietarius, from Late Latin, adjective (see 2proprietary)

First Known Use: 15th century



adjective pro·pri·e·tary \prə-ˈprī-ə-ˌter-ē\

Simple Definition of proprietary

  • : of or like that of an owner

  • : used, made, or sold only by the particular person or company that has the legal right to do so

  • : kept private by an owner

Full Definition of proprietary

  1. 1 :  of, relating to, or characteristic of an owner or title holder <proprietary rights>

  2. 2 :  used, made, or marketed by one having the exclusive legal right <a proprietary process> <proprietary software>

  3. 3 :  privately owned and managed and run as a profit-making organization <a proprietary clinic>

Examples of proprietary

  1. By allowing less favorable results to remain buried, the agency puts proprietary interests ahead of the public interest, and doctors and the public come to believe prescription drugs are better than they are. That should stop. —Marcia Angell, New York Review of Books, 8 June 2006

  2. It is a proprietary faith: no one better tell me what to do with my own land. —Lance Morrow, Time, 11 Sept. 2000

  3. Many veterans have adopted a proprietary attitude toward the war, and they can get a bit belligerent about it. —Nicholas Proffitt, New York Times Book Review, 21 May 1989

  4. The investors have a proprietary interest in the land.

  5. The computer comes with the manufacturer's proprietary software.

  6. Merriam-Webster is a proprietary name.

  7. The journalist tried to get access to proprietary information.

Origin of proprietary

Late Latin proprietarius, from Latin proprietas property — more at property

First Known Use: 1589

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February 6, 2016

an official order, decree, or edict

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