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

Core functions like messaging and payments were given priority, but more complex features—such as Moments, Mini Programs, voice and video calls, and third-party plugins—needed to be re-engineered from the ground up. —Vivian Toh, Forbes.com, 22 July 2025

The vehicles will be owned and operated by Uber or its third-party fleet partners. —Richard Brack, Austin American Statesman, 22 July 2025

Noun

Badges purchased from third parties or resellers are invalid. —Greta Cross, USA Today, 24 July 2025

Redirecting to third parties often means handing off the customer and the data that powers growth. —Nandan Sheth, Forbes.com, 21 July 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