/kəmˈpleɪnt/ – noun
Definition: 1. sự phàn nàn, sự than phiền, sự khiếu nại;
2. sự kiện tụng;
3. đơn kiện, lời buộc tội chính thức.
A more thorough explanation: In legal terms, a complaint is a formal legal document filed by a party in a civil case that sets out the facts and legal arguments supporting their claim against another party. It initiates a lawsuit and typically outlines the allegations and the relief sought by the plaintiff.
Example: The plaintiff filed a complaint against the defendant, alleging breach of contract.