"Stop snitchin'" means that some people believe that it's not okay to tell on someone else. Imagine you have a toy that someone else wants to play with. They try to take it from you, but you don't want them to because it's yours. If you tell an adult what happened, the other person might get in trouble. But some people who say "stop snitchin'" think that you shouldn't tell the adult because the other person might get mad at you or hurt you. They might not think it's fair that you told on them. But telling an adult can help keep you safe and make sure that everyone is being fair and following the rules. So it's always okay to tell someone if you feel like you're in danger or you see someone else doing something wrong.