The person whose job it is to cut up and sell meat is called a butcher. Your grandmother might go to the butcher once a week to buy pork chops.
A butcher is an expert at preparing cuts of meat and poultry in a butcher shop or the meat section of a supermarket. You can also call a person whose job is slaughtering farm animals a butcher. Because this is a fairly bloody, gory occupation, the word is also used to mean a cruel, ruthless murderer. And when you really mess something up, you can also be said to butcher it — like the way you butchered that poem when you tried to recite it from memory.