In cooking, to tenderize is to prepare meat so it's more easily chewed, or tender. One way to tenderize meat is to roast it at a low temperature for a long time.
There are many different techniques cooks use to tenderize meat. They might marinate it in an acidic liquid, pound it repeatedly before cooking, or brine it in a saltwater solution, for example. All of these methods result in a more tender piece of meat that can be cut and chewed easily. Any tool or substance used to tenderize meat is called a tenderizer.