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

We don’t actually know 100% what she/he said or did — only that she reacted strongly and that response was reported to a third party.

From MarketWatch • Apr. 13, 2026

“A third party that agreed to pay his legal fees and costs has refused to pay, leaving Kay’s current counsel with more than $130,000 in unpaid fees and out-of-pocket expenses,” Gerger wrote.

From Los Angeles Times • Apr. 7, 2026

Earlier this week, Two Harbors said a CrossCountry bid worth $10.70 a share was superior to its deal with UWM and said it had also received a bid from an additional third party.

From The Wall Street Journal • Mar. 27, 2026

Any prospective heirs will then have to rely on their own skills to build their finances, rather than relying on a third party.

From MarketWatch • Mar. 16, 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