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

In the proposed settlement announced Friday, PG&E agreed to pay a $21-million penalty to California’s general fund, and up to $1 million to a third party that will examine the utility’s policies.

From Los Angeles Times ● Jul. 12, 2026

In most cases, the collector may not discuss your debt, ask the third party to pay it, or repeatedly contact that person.

From MarketWatch ● Jul. 9, 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

The court heard that Law then asked a third party who lived in the US to contact authorities to inform them what had happened.

From BBC ● Jun. 12, 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