proprietary

American  

[pruh-prahy-i-ter-ee] / prəˈpraɪ ɪˌtɛr i /

adjective

1. belonging to a proprietor.

2. being a proprietor; holding property.

   the proprietary class.

3. pertaining to property or ownership.

   proprietary wealth.

4. belonging or controlled as property.

5. (of a brand name, product, service, formula, etc.) protected by a patent, copyright, or trademark.

   proprietary drugs; a proprietary name; a proprietary logo; a proprietary blend of ingredients.

6. privately owned and operated for profit.

   proprietary hospitals.

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noun

proprietaries plural

1. an owner or proprietor.

2. a body of proprietors.

3. American History. the grantee or owner, or one of the grantees or owners, of a proprietary colony.

4. ownership.

5. something owned, especially real estate.

6. a proprietary medicine.

7. Also called proprietary school.  a school organized as a profit-making venture primarily to teach vocational skills or self-improvement techniques.

proprietary British  

/ prəˈpraɪɪtərɪ, -trɪ /

adjective

1. of, relating to, or belonging to property or proprietors

2. privately owned and controlled

3. med of or denoting a drug or agent manufactured and distributed under a trade name Compare ethical

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noun

1. med a proprietary drug or agent

2. a proprietor or proprietors collectively

3. 1. right to property

   2. property owned

4. Also called: lord proprietary.  (in Colonial America) an owner, governor, or grantee of a proprietary colony

Other Word Forms

• nonproprietary
  adjective
• proprietarily
  adverb

Etymology

Origin of proprietary

1400–50; late Middle English (noun) < Medieval Latin proprietārius owner, noun use of Late Latin: of an owner, of ownership. See propriety, -ary

Explanation

If you own something, especially something of value, then you have proprietary rights. The word is most often used in relation to new inventions or patents. Proprietary refers to property: things that are owned by individuals or businesses. People talk about proprietary drugs, proprietary software, and other things that can only be made and sold by those who discovered or created them. A proprietary claim is usually protected by trademark or copyright. When you say you have a proprietary right to something you're saying to everyone else: "Hands off! This is mine." Years ago, owners of small mom-and-pop stores were known as proprietors.

Example Sentences

“By virtue of his position with Joby, Kivork had access to confidential and proprietary information,” the complaint said.

From Los Angeles Times • May 20, 2026

He uses public and proprietary data and public records to dig into how financial, business, economic, legal and regulatory issues affect Americans' lives.

From The Wall Street Journal • May 20, 2026

Arkeus’s AI-powered platform gathers and interprets optical data from proprietary sensors, including light not visible to the human eye.

From The Wall Street Journal • May 15, 2026

It’s billed as different from “your average rib sandwich,” with ribs that have been hand-deboned, marinated in a proprietary barbecue-sauce blend with apple-cider vinegar, then slow-cooked for nine hours.

From MarketWatch • Apr. 29, 2026

Durham had clasped King to its heart nearly five years before he had been awarded the Nobel Peace Prize, and so residents couldn’t be blamed for assuming a proprietary interest in the reverend’s illustrious career.

From "The Best of Enemies" by Osha Gray Davidson

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