In legal terms, how is a "complaint" defined?

A complaint, in legal terms, is defined primarily as a written grievance. This document serves as the formal initiation of a lawsuit and outlines the plaintiff's claims against the defendant. It details the facts of the case, the legal basis for the lawsuit, and what relief the plaintiff is seeking from the court. The written nature of the complaint is crucial because it ensures that there is an official record of the allegations and claims, providing a clear framework for the court to address the issues presented.

The other options do not capture the significance or formal requirements of a complaint in the legal context. While a document requesting investigation may be related to initiating legal processes, it does not specifically describe the formalities inherent to a complaint. An informal dispute is not legally binding and does not follow the necessary legal procedures. Similarly, a verbal accusation lacks the formal structure and record-keeping that a written complaint provides, making it ineffective in the context of legal proceedings where clarity and documentation are essential.