Legal glossary

Joinder

Joinder: Combining parties or claims in a single lawsuit.

Joinder — a magnifying glass over legal documents

What joinder means

Put simply, joinder is part of the working vocabulary of a civil case. The short definition above covers the usual meaning. Still, a specific rule, statute or contract can give it a narrower meaning. For that reason, check how it is used in your own documents.

Where joinder comes up

For example, the term appears in these procedures:

How to research the term

Start with the primary source. For example, if joinder appears in a federal rule, read the rule itself and its official notes. After that, check your court’s local rules and any standing orders from the judge. In addition, search recent decisions from your own state or federal district. They show how courts read joinder in practice. Because state rules often differ, our state procedures guide links to each state’s official rules. Above all, make sure the version you read is still in force.

You can read the official rule text online for free.

Related legal terms

  • Intervention: a procedure that lets a nonparty become a party to an existing lawsuit.
  • Irreparable harm: harm that cannot be adequately remedied by money damages after the fact.
  • Judgment: the court's final decision determining the rights of the parties.
  • Judgment as a matter of law: a ruling that a reasonable jury would not have a legally sufficient evidentiary basis to find for a party on an issue.

Why precise terms matter

Courts read legal terms closely. As a result, knowing the exact meaning of a word helps you follow orders, rules and filings. Each glossary entry on Lawtopolis is short on purpose and links to the pages where the term is used.

Sources

Sources last reviewed: 2026-10-23

Lawtopolis provides legal information and education, not legal advice. Using this site does not create an attorney-client relationship. Laws and court rules vary by jurisdiction and change over time; verify every authority against the official source and consult a licensed attorney in your jurisdiction about your situation.