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 firm did not specify how people will be asked to apply, but the program will be administered by an independent third party unaffiliated with the company, the district attorney’s office said.

From Los Angeles Times ● Aug. 24, 2026

Spirit said it is “engaging a third party to deidentify the data and certify that the data sold at auction is compliant with applicable privacy laws and regulations.”

From The Wall Street Journal ● Aug. 19, 2026

At that level of investment, Moore said the “sophisticated third party investor groups” are calling the shots, which should assuage fears that deals are being “purely driven by circular motivations.”

From MarketWatch ● Aug. 11, 2026

Allowing a third party to monitor a ceasefire is one way to reduce violations and disputes.

From Los Angeles Times ● Aug. 7, 2026

Any third party whom you might make their commander cannot immediately seize enough authority to harm you.

From "The Prince" by Niccolò Machiavelli

Related Words

• mediator