noun
Usage: often capitalized G
: a slender nematode worm ( Dracunculus medinensis ) attaining a length of several feet, occurring as an adult in the subcutaneous tissues of man and various mammals in parts of Africa and other warm countries, and having a larva that develops in small freshwater crustaceans (as cyclops) and when ingested with drinking water passes through the intestinal wall and tissues to lodge beneath the skin of a mammalian host and there mature