Plantiff
In a criminal case it is the accuser. In a civil case - think Judge Judy - it is the Plaintiff
The PLAINTIFF is the party who files (brings) the lawsuit.
The aggrieved party in a lawsuit is the plaintiff
That the defendant injured, or caused them some damage, monetary or physical.
Petitioner
Petitioner
In civil proceedings, a party's status refers to their role and position in the case. The main parties in civil proceedings are the plaintiff (the party initiating the lawsuit) and the defendant (the party being sued). Other potential parties include third-party defendants (brought into the case by the defendant), intervenors (who have a legal interest in the case), and amicus curiae (who provide information or arguments to assist the court).
A person or Party begins a civil case against another party by a complaint being introduced. This complaint must be shown to the Court House where it is decided to be ruled or not. To begin a civil case or complaint against another party, the complainant/plaintiff must file a lawsuit/complaint in court to initiate the case. This would also involve paying the proper filing fees and yes, often, a lawyer would be necessary in order to prepare your pleading.
In both cases, the moving party bears the burden of proof. In a criminal case, that is the government. In a civil case, that is the plaintiff.
The party who initiates a legal case is known as the plaintiff in a civil case or the prosecution in a criminal case. They are the ones bringing the case to court and seeking a resolution or remedy for the legal issue at hand.
In a civil case they would be the plaintiff.In a criminal case they would be the prosecution (the Crown).In an appeal they would be the appellate.
The party that brings the case, or files a petition for writ of certiorari, is called the Petitioner. The opposing party is called the Respondent.