coparty

Coparty is a term formed from the prefix co- and the noun party, used to describe shared involvement by two or more parties in a single matter or event. Its precise meaning varies by context, but it generally denotes joint participation or joint responsibility.

In legal usage, coparty (often written as co-party or co-party plaintiff/defendant) refers to a person or entity that shares a common interest in the outcome of a case. Co-parties may be plaintiffs or defendants and can participate in joint pleadings, coordinated strategy, or consolidated proceedings under court rules. Many jurisdictions prefer the hyphenated form co-party, while coparty appears in some texts or nonstandard usage.

Outside the law, coparty can describe a party or event organized or attended by multiple hosts who share responsibility for planning, budgeting, or execution. In contemporary English, informal references to a jointly organized event more commonly use terms like co-hosted party or jointly hosted event, with coparty being less common.

Etymology and usage vary by region and style guide. The general sense remains one of shared participation or shared responsibility among multiple parties. When writing, users should consider local conventions or style preferences, such as co-party or co-hosted, to ensure clarity and consistency. See also co-party, co-host, joint party.