a nematode worm (Dracunculus medinensis) of tropical Africa and S Asia, parasitic as an adult in the subcutaneous tissues of humans and other mammals: the female can reach a length of c. 90 cm (c. 3 ft)
See Guinea worm in American Heritage Dictionary 4
noun
A long threadlike nematode worm (Dracunculus medinensis) of tropical Asia and Africa that is a subcutaneous parasite of humans and other mammals and causes ulcerative lesions on the legs and feet.