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.

---

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

---

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

Accordingly, the deal is now specifically fashioned as a deal with a third party, North American Blue Energy Partners.

From Los Angeles Times ● Oct. 6, 2026

China's defence ministry added that the site would be "maintained for normal operations by both sides" and did not target any third party.

From Barron's ● Oct. 2, 2026

This was an agreement between City and a third party called Fordham which was, according to the ruling, "little more than a front".

From BBC ● Sep. 29, 2026

First off, you have to trust your adult children or any third party to give someone either a durable or medical power-of-attorney document.

From MarketWatch ● Sep. 24, 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