third-party

1 of 2

adjective

third-par·​ty ˈthərd-ˈpär-tē 

1

: of, relating to, or involving a third party

third-party insurance

2

: of, relating to, or being software that is created by a vendor to be compatible with the products of another vendor

third party

2 of 2

noun

1

: a person other than the principals

a third party to a divorce proceeding

insurance against injury to third parties

2

a

: a major political party operating over a limited period of time in addition to two other major parties in a nation or state normally characterized by a two-party system

b

: minor party

Examples of third-party in a Sentence

Recent Examples on the Web

Adjective

Under strain Space Force officials are eager to exit the business of warning third-party satellite operators, including rivals such as Russia and China, of possible collisions in orbit. —ArsTechnica, 10 July 2025

The company has also started introducing dubious features like Blood Vision, which requires you to take a blood test from a third-party tester. —Simon Hill, Wired News, 10 July 2025

Noun

The risk and the sheer headache of bringing in a third party just aren't worth it. —Thanh Pham, Forbes.com, 1 July 2025

Bramlette is set to begin his new role on July 9, overseeing CSC’s daily operations and managing relationships with third parties, including Deloitte and LBi Software. —Daniel Libit, Sportico.com, 30 June 2025

Word History

First Known Use

Adjective

1901, in the meaning defined at sense 1

Noun

1641, in the meaning defined at sense 1

Kids Definition

third party

noun

1

: a person other than the main participants

a third party to the legal proceedings

2

a

: a political party operating usually for a limited time in addition to the two major parties in a 2-party system

b

: minor party

Legal Definition

third party

see party sense 1a, b