I think, we, adults, are too serious. These are just words. The more we forbid them, the more the kids will use them. I would not punish (I never do) and instead listen to your son about his experience. He shouldn't be an anger, that's a huge burden no one can live up to.
Ask him about the feelings that prompt his rough words and connect with him. He may have some anger issues. And self-expression needs an outlet.

dont worry boys will be boys if it keeps happening get his dad to have a man to man chat.If you have this trouble after the man to man chat ask his headteacher to have a firm but fair talk
yours sincerly
lilly void(0);
void(0);