third party

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third party

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• 3rd party, 3d party

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third party (plural third parties)

1. (business, commerce) Someone not directly involved in a transaction; an entity beyond the seller (first party) and customer (second party).

   A seller may employ a third party to perform specific services to augment the value of a product, such as packing and distribution.

2. (law) Someone only incidentally or tangentially connected to an incident or dispute; someone other than the principals; a bystander or independent witness.
3. (politics, chiefly US) A political party in opposition to the main parties in a two-party system.
   • 2010, Duncan Watts, Dictionary of American Government and Politics, →ISBN, page 177:

     Those who belong to the Libertarian Party serve a much larger pro-liberty community and have the specific mission of electing libertarians to public office. They traditionally billed themselves as 'America's largest third party'.

• third-party (adjective)
• third-party (verb)

• two-party system
• three-party system
• third-party