A LITIGANT is an individual or organization involved in a legal dispute, and a PARTY is a person or group of people involved in a legal action. The term 'plaintiff or defendant' refers to the two main roles in a civil lawsuit, with the plaintiff being the person or entity initiating the lawsuit and the defendant being the person or entity responding to the lawsuit. In other words, a LITIGANT or PARTY in a civil lawsuit can either be a plaintiff or a defendant.