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

Derived Forms

• nonproprietary
  adjective
• proprietarily
  adverb

Inflected Forms

Nouns

• proprietaries
  plural

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

The startup company, which says it has completed about 15 jobs in three states, uses proprietary water-purification technology that includes a contraption the size of a small trailer.

From The Wall Street Journal • Jun. 28, 2026

Now, Cursor has access to the treasure trove of computing power offered by SpaceX’s Colossus data centers and fresh capital to continue developing its platform and proprietary coding model Composer.

From MarketWatch • Jun. 19, 2026

Its proprietary AI analyzes the information to identify conditions that can range from the minor to—in at least one case—something as serious as a blocked artery.

From The Wall Street Journal • Jun. 16, 2026

To reduce its reliance on competitors, in late 2025, Cursor introduced its own proprietary AI agent, Composer, alongside other third-party coding assistants.

From Los Angeles Times • Jun. 16, 2026

“Netscape helped to guarantee that these open protocols would not be proprietary by commercializing them for the public,” said Andreessen.

From "The World Is Flat" by Thomas L. Friedman

Related Words

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