Term: Leech

Archaic term for a healer, such as a doctor. Some early doctors believe that there were “evil humors” in the blood, and by draining the blood you could remove the evil humors that caused disease. Sometimes, leeches were used in this process.

A small, worm-like creature with a sucker that allows it to attach to its victim and consume its blood. Groups of leeches can consume enough blood from a single source to cause death. As mentioned, leeches used to be used by doctors to drain small amounts of blood from people in order to remove “evil humors.” Today, leeches kept under sterile conditions are again being used for a variety of reasons, their bite producing an anticoagulant, a vasodilator, and a local anesthetic. Some people believe George Washington died from the application of too many leeches; however, shortly before his death, he was bled by doctors and lost five pints of blood, about half of the body’s supply, as treatment for a throat infection. He either died from the infection or loss of blood (or both), but it is unlikely that that much blood loss could have been caused by leeches.