Definition of "proprietary" []

• Of, relating to, or suggestive of a proprietor or to proprietors as a group: had proprietary rights; behaved with a proprietary air in his friend's house. (adjective)
• Exclusively owned; private: a proprietary hospital. (adjective)
• Owned by a private individual or corporation under a trademark or patent: a proprietary drug. (adjective)
• A proprietor. (noun)
• A group of proprietors. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "But after Lehman went bankrupt, former Federal Reserve Chairman Paul Volcker often talked about proprietary trading at banks, and the term "proprietary" became confusing (to say nothing of, dare we say, sullied.) "They wanted to distinguish what they do from other firms that use the term proprietary trading," explains Overdahl."
• "Most mother boards for laptops are what they call proprietary, meaning that each company that make laptop mother boards have a unique configuration for the Ram slots and cpu location, etc."
• "That's long been a sticking point in the debate, with companies expressing reluctance to publicly disclose what they call their proprietary fracking cocktails, and environmental groups and other opponents calling that reluctance a specious attempt to frustrate efforts that would link the chemical formulas to groundwater contamination."