A prosecutor is someone who tries to prove that a person has done something wrong and should be punished. They often work for the government.
Imagine you're watching a TV show about a detective trying to solve a crime. The detective gathers evidence, talks to witnesses, and presents their case in court. That's basically what a prosecutor does - they gather facts and present them to a judge or jury to prove that someone is guilty of a crime. This can be in a big city, a small town, or even internationally.
To start criminal proceedings against.
Example: to prosecute a man for trespass, or for a riot
