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

Patients encounter it when third-party scheduling tools reflect outdated availability. —Teresa MacKintosh, Fortune, 13 June 2026

Rather than relying entirely on manual data entry, companies can use on internet-of-things sensors, smart contracts, or other third-party verification tools to keep the record up to date. —Sean Stein Smith, Forbes.com, 12 June 2026

Noun

Its open systems architecture facilitates integration with third party sensors and warheads. —Aditya Jadhav, Interesting Engineering, 18 June 2026

More than 100 people showed up for a party in the 300 block of Westchester Way on June 13, when city officials say a private residential pool was rented out to a third party, violating zoning regulations. —Joseph Buczek, CBS News, 18 June 2026

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 also:

party sense 1a, b