What is the term for a written request that initiates a civil suit?

The term for a written request that initiates a civil suit is referred to as a complaint. In the context of legal proceedings, a complaint serves as the formal document filed by the plaintiff to outline their case against the defendant. It details the basis for the lawsuit, the facts supporting the claim, and the relief or damages sought.

A complaint initiates the civil litigation process and must be served to the defendant, who will then respond. This document is crucial as it sets the foundation for the case and informs the court and the defendant of the nature of the allegations.

In contrast, other terms like motion, plea, and summons serve different purposes in the legal process. A motion is a request made to the court for a specific ruling or order, a plea typically pertains to criminal proceedings regarding a defendant's response to charges, and a summons notifies a defendant of a legal action against them and compels their presence in court but does not outline the claim itself.