third party

American  

noun

third parties plural

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

Other Word Forms

Noun Inflected Forms

• third parties
  plural

Etymology

Origin of third party

An Americanism dating back to 1795–1805

Example Sentences

See Examples For:

third party

The DPS letter said inaccurate information recorded about Lorraine on police systems had been shared with others and defamatory information about her was passed by a third party to her GP.

From BBC ● Jul. 2, 2026

With a “discretionary trust,” you appoint a trusted third party, like a bank manager or lawyer who is also likely to be a professional fiduciary, as the trustee.

From MarketWatch ● Jun. 23, 2026

As third party delivery services such as DoorDash grew in popularity, Pizza Hut fell behind without the advantage of delivery convenience, said Aneurin Canham-Clyne, a reporter for trade publication Restaurant Drive.

From Los Angeles Times ● Jun. 16, 2026

Arcade’s technology also can run within a customer’s private environment rather than being hosted externally by Arcade or another third party, thereby bypassing many security and compliance concerns.

From The Wall Street Journal ● Jun. 15, 2026

"Yes, sir, he put through the sale—though he made it clear that he was buying Soldier Island for a third party, unnamed."

From "And Then There Were None" by Agatha Christie

Related Words

• mediator