What is "interdictum"

In Roman law, an interdictum was an order issued by a praetor (or, in the provinces, a proconsul) at the request of a claimant and addressed to another person, imposing a requirement either to do something or to abstain from doing something.

The interdictum, like the modern injunction, is a quick decision process designed to protect existing situations. Its procedure is summary. What the plaintiff alleges is taken as true; if his claims are not true, the defendant will disregard the order and defend his right in the subsequent ordinary trial.