hamstring

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Any of the tendons at the rear hollow of the human knee.
2. n. The hamstring muscle.
3. n. The large tendon in the back of the hock of a quadruped.
4. v. To cut the hamstring of (an animal or a person) and thereby cripple.
5. v. To destroy or hinder the efficiency of; frustrate: "These worthwhile books are often hamstrung by unimaginative formats and inaccurate art" ( Don Lessem).

Century Dictionary and Cyclopedia

1. n. In human anatomy, 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 semitendinosus, semimembranosus, 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. n. 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 tendo Achillis, 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.
3. To cut the hamstrings of, and thus lame or disable.
4. In whaling, to cut the muscle or tendons of the small of the whale, so as to render the flukes useless and make the animal helpless. It is done with the fluke-spade when a boat is hauled up alongside a running whale.

Wiktionary

1. n. anatomy One of the great tendons situated in each side of the ham, or space back of the knee, and connected with the muscles of the back of the thigh.
2. n. informal The biceps femoris muscle.
3. v. transitive To lame or disable by cutting the tendons of the ham or knee; to hough; hence, to cripple; to incapacitate; to disable.

GNU Webster's 1913

1. n. (Anat.) One of the great tendons situated in each side of the ham, or space back of the knee, and connected with the muscles of the back of the thigh.
2. v. To lame or disable by cutting the tendons of the ham or knee; to hough; hence, to cripple; to incapacitate; to disable.

WordNet 3.0

1. v. cripple by cutting the hamstring
2. n. one of the tendons at the back of the knee
3. v. make ineffective or powerless