hamstring

(ham’string), n. 1. In human an at., the tendon of a muscle which bounds the ham, or space behind the knee on either side above the middle of the popliteal space. The outer hamstring is single, and is the tendon of the biceps muscle; there are three inner hamstrings, the tendons of the semi ten dinos us, semi mem bra nos us, and gracilis muscles, with which a fourth, that of the sartorius, may be reckoned. These muscles flex the leg upon the thigh, and, with the exception of the sartorius and gracilis, extend the thigh upon the trunk. 2. In ordinary language, the great tendon or sinew at the back of the so-called knee or hock of the hind leg of a quadruped. It is the ten do A chillis, or tendon of the gastrocnemius muscle, corresponding to that at the back of the human ankle, and extends the foot or pes upon the leg or crus. See cut under horse.