A courtroom is the room in a law court where a case is heard and judged. The judge sits at the front; the lawyers speak; the accused and the witnesses sit or stand where they are told; and the public may watch from the back if the court allows it. News reports say in the courtroom when they mean during the trial itself, not in the corridors or outside on the steps. It is a plain, factual word — newspapers, films, and ordinary people all use it. It names one room, not the whole court building.