In anatomy, the term ligament usually means fibrous tissue that connects bones to other bones or cartilages.
In this use, a ligament is a short band of tough fibrous connective tissue composed mainly of long, stringy collagen fibres. Ligaments connect bones to other bones to form a joint. They do not connect muscles to bones; that is the function of tendons. Some ligaments limit the mobility of articulations, or prevent certain movements altogether.