A meatball is meat that is ground up (finely cut), mixed with other ingredients, then shaped like a ball. Most meatballs are made out of beef. Meatballs can also be made out of chicken, fish, or other kinds of meat. The other ingredients (parts) are usually bread, onion, and eggs. Meatballs can be cooked by frying, baking, or steaming them. Meatballs are sometimes served with pasta or in a sauce.