adj

proprietary

pruh-PREYE-uh-tuh-ree

adj

Owned exclusively by a company or individual, often protected by patent, trademark, or trade secret.

"The software uses a proprietary file format that competitors can't open."

"The recipe is a closely guarded proprietary secret."

Showing a sense of ownership or possessiveness over something.

"He grew proprietary about the project after leading it for so long."

How to Use Proprietary

Learner’s notes

In plain EnglishPrivately owned and controlled — often used for software, technology, or formulas that only one company can use or sell.

Common pairings

proprietary software proprietary technology proprietary blend

more proprietary comparative, proprietaries plural, most proprietary superlative

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The software uses a _____ file format that competitors can't open.

From French propriétaire, from Latin proprietarius, related to proprietas ("property, ownership").

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