Something to chew on is a phrase that can refer to a variety of items, including CUD (3 letters), FOOD (4 letters), BONE (4 letters), COCA (4 letters), ORT (3 letters), GUM (3 letters), and SOLIDFOOD (9 letters). CUD is an acronym for CUD-chewing, which is the process of an animal such as a cow or sheep chewing its FOOD more than once. FOOD is a general term for any edible substance that provides nutrition to an organism. BONE is a hard, calcified tissue found in many animals that provides structure and protection to the body. COCA is a plant native to South America whose leaves are used to make cocaine. ORT is a small piece of FOOD left over after a meal. GUM is a type of sticky substance made from tree sap that is often chewed for pleasure. SOLIDFOOD is a type of FOOD that is not liquid or semi-liquid. All of these items can be considered something to chew on.