One entry found for leech.
Main Entry: leech
Etymology: Old English l[AE]ce "doctor, physician" 1: any of numerous flesh-eating or bloodsucking usually flattened worms that are made up of segments and have a sucker at each end 2: a person who clings like a leech to another person for advantage or gain : PARASITE Word History In the early days of medicine, a physician, known in Old English as a l[AE]ce, often drew blood from patients. These doctors acted in the belief that good health depended on a balance of four controlling fluids in the body. These four fluids were called humors, and one of them was blood. In those days physicians believed that a person became ill if there was too much blood or too little of any of the other humors in the body. Thus they used a controlled bleeding of the patient, or bloodletting as it was called, to balance the humors. An easy way to do this was to attach bloodsucking worms to the body. These worms are common in all parts of the world and especially in marshes and swamps. Today we call these sucking worms leeches, taking the name from those ancient doctors who used them so often.