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

These payments were seemingly facilitated by a third party.

From BBC

The same problem arises whenever third parties spend on your behalf—healthcare, corporate procurement, government programs.

From The Wall Street Journal

When asked about Defense Secretary Pete Hegseth sharing classified information on an unsecured third party messaging app, he replied, “I don’t know anything about it.”

From Salon

The Times reviewed text messages among firefighters and a third party, sent in the weeks and months after the fire, describing the crew’s concerns.

From Los Angeles Times

In its report, the regulator said Horizon Radio's web stream and DAB transmission were provided by third parties.

From BBC

Related Words

• mediator