third party

American  

noun

1. any party to an incident, case, quarrel, etc., who is incidentally involved.

2. (in a two-party system) a political party formed as a dissenting or independent group from members of one or both of the two prevailing major parties.

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third party British  

noun

1. a person who is involved by chance or only incidentally in a legal proceeding, agreement, or other transaction, esp one against whom a defendant claims indemnity

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adjective

1. insurance providing protection against liability caused by accidental injury or death of other persons or damage to their property

   third-party insurance

Etymology

Origin of third party

An Americanism dating back to 1795–1805

Example Sentences

The company believes this LLM will give it a competitive advantage and control over AI costs, “with little to no reliance on third party LLMs,” Abrahami added.

From Barron's • May 13, 2026

Genesis Minerals “remains the obvious third party with clear strategic benefits in the Leonora region,” Hissey says.

From The Wall Street Journal • May 5, 2026

Vodafone has indicated that the footfall technology was owned and managed by a third party company, which it says investigated issues raised.

From BBC • May 5, 2026

According to investigators, Mr. Evans bought the abortion pills from a third party.

From The Wall Street Journal • May 4, 2026

Somebody, a third party, agreed the fishing had gone sour, the bank seemed all dried up real sudden, he’d been thinking on fishing at Elliot Head, couldn’t tell but maybe things was better there.

From "Snow Falling on Cedars: A Novel" by David Guterson

Related Words

• mediator