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

North Carolina, where the Ammels lived, is one of just a handful of states with a “homewrecker law” that allows a jilted spouse to sue a third party for damages for a marital breakup.

From The Wall Street Journal • Apr. 18, 2026

“The aim of the measures is to allow third party online search engines, or ‘data beneficiaries’, to optimize their search services and contest Google Search’s position,” the Commission said.

From MarketWatch • Apr. 16, 2026

“Plaintiffs will always have the ability to claim that they’re not suing based on third party content, they’re suing on the way third party content was presented.”

From Salon • Apr. 16, 2026

“A third party that agreed to pay his legal fees and costs has refused to pay, leaving Kay’s current counsel with more than $130,000 in unpaid fees and out-of-pocket expenses,” Gerger wrote.

From Los Angeles Times • Apr. 7, 2026

A man that thinks anything he dont understand all about must be crooked and that first chance he gets he’s morally bound to tell the third party what’s none of his business to tell.

From "The Sound and the Fury" by William Faulkner

Related Words

• mediator