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

Academica is a third-party charter school support organization that provides operational support while the school’s governing board maintains authority over academics, staffing and curriculum. —Nicole Buss, Sacbee.com, 13 Mar. 2026

Instagram’s lack of caption linking has led people to use third-party services like Linktree, which allow creators to add external links in their bios. —James Peckham, PC Magazine, 13 Mar. 2026

Noun

Publicly exposing your debt Debt collectors cannot publicly shame borrowers or disclose debt information to unauthorized third parties. —Angelica Leicht, CBS News, 17 Mar. 2026

Lawyers already are barred under the State Bar’s rules from allowing a third party to dictate case strategy and are barred in many cases from sharing legal fees with a nonlawyer. —Rebecca Ellis, Los Angeles Times, 17 Mar. 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