Courts often award damages to parties when they have been aggrieved. That's not the only thing a Court can award, however. Sometimes, they award injunctions. These are orders by a court to DO something or STOP doing something. It is said a person is "enjoined" from an conduct, and the court's order enjoining them is the "Injunction" itself. Injunctions are usually ordered early in a case. That is because injunctions are supposed to be to stop one party from "irreparable harm." This is the kind of harm that money damages cannot substitute.
For example, in this article you can read about a court enjoining a Texas school district from using what the union argues is an illegal teacher evaluation process. The "irreparable harm" in that case would be that their union members would be evaluated under a new and illegal system, and these teachers will never be able to go back in time to get evaluated during their review period under an appropriate system.
As you can see, it can be complicated and nuanced! But legal issues are often complicated. Please contact our office if you are enjoined and you don't believe it is appropriate or need an injunction.