It means "servant" basically, and it's about an apparent difference in social classes. If I ask a barista "you can also mow my lawn if you want to make some mon

It means "servant" basically, and it's about an apparent difference in social classes. If I ask a barista "you can also mow my lawn if you want to make some money" it's an insult that the barista can't even refute, but if I ask my friend the same, he'll take it as a joke.