- Failure to name as a party one that legally should have been named, as in a lawsuit.
- Failure to include as part of a cause of action or suit a claim that legally should have been made.
- In <em>law</em>, the omission to join, as of a person as party to an action.
- The omission of some person who ought to have been made a plaintiff or defendant in a suit, or of some cause of action which ought to be joined.
- The <xref>omission</xref> of a <xref>party</xref> that was necessary to an <xref>action</xref>