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

Apple examines each application and each update of every third-party app, and if these don’t meet Apple’s definition of acceptable, then they are not allowed to be installed. — Ewan Spence, Forbes.com, 6 July 2026

The company provides services for setting up Gold IRAs by working with third-party custodians and depositories. — Jamela Adam, USA Today, 5 July 2026

Noun

Even if a third party such as Oman collected the fees, tolls would likely still breach international maritime laws, including the United Nations Convention on the Law of the Sea (UNCLOS), allowing insurers to reject voyages or terminate cover. — David Goldman, CNN Money, 15 July 2026

Offer availability, placement, and display are determined by the third party and may be influenced by compensation and other factors. — Liz Knueven, CNBC, 15 July 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