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

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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

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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

See Examples For:

proprietary proprietaries

Companies needn’t worry about sharing proprietary data if they use open models.

From The Wall Street Journal ● Oct. 26, 2026

Goldman maintains a proprietary index that tracks the relative performance of the stocks most popular with hedge funds against that of the most-shorted names.

From MarketWatch ● Oct. 23, 2026

“What was interesting about this conglomeration is that nobody was feeling territorial or proprietary about an instrument or a contribution.”

From Los Angeles Times ● Oct. 21, 2026

Across the small sector, these services draw on a usually unspecified mix of third-party language models and proprietary technology.

From Slate ● Oct. 16, 2026

The thought of ceding to the army a project in which the foundation had such an immense stake stirred Fosdick’s proprietary blood.

From "Big Science" by Michael Hiltzik

Though Evergreen bought Intermountain Aviation, one of Doole's CIA "proprietaries," in 1975, the company insists that it has had nothing further to do with the agency.

From Time Magazine Archive

With the spread of the influenza epidemic pernicious drug vendors cried new merits for their proprietaries.

From Time Magazine Archive

At last Franklin won the king's signature to a bill by the terms of which the surveyed lands of the proprietaries should be assessed, and, his business accomplished, he returned to Philadelphia.

From Franklin's Autobiography (Eclectic English Classics) by Benjamin Franklin

Difficulties arose between the proprietaries and government of the province of Pennsylvania, which were referred to the mother country for adjustment.

From Sages and Heroes of the American Revolution by L. Carroll Judson

With this war against France began the struggle of the Assemblies and the proprietaries on the question of taxing the estates of the latter.

From Heroes of Science: Physicists by William Garnett

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