: a branch of mathematics or of symbolic logic that deals with the nature and relations of sets. â set theoretic adjective. See set theory defined for kids. ADVERTISEMENT.
Discrimination Lawsuit. A lawsuit is a civil action brought before a court of law in which a plaintiff, a party who claims to have received damages from a defendant's actions, seeks a legal or equitable remedy. The defendant is required to respond to the plaintiff's complaint.
The person who initiates a lawsuit by filing a complaint is called the plaintiff. When the document that initiates a lawsuit is called a petition rather than a complaint, the initiating person is usually referred to as the petitioner rather than the plaintiff.