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

Cerner Health, a third-party electronic medical record vendor, notified Atrium in December that patients’ personal or health information may have been accessed by an unauthorized party, Atrium said. —Charlotte Observer, 8 May 2026

The Future of the Digital Counter In an era where the digital shelf is often the leading point of discovery, beauty and luxury brands can no longer afford to treat third-party retail as a secondary consideration. —Fairchild Studio, Footwear News, 8 May 2026

Noun

The deal is available for in-restaurant orders at the register only and cannot be redeemed via kiosk, online or third party. —Gabe Hauari, USA Today, 6 May 2026

If a third party is prompting you to comment, then Miss Manners strongly urges you to thank them — and do nothing of the sort. —Judith Martin, Sun Sentinel, 6 May 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