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echinococcus e·chi·no·coc·cus (ĭ-kī'nə-kŏk'əs)
n. pl. e·chi·no·coc·ci (-kŏk'sī', -kŏk'ī')
A tapeworm of the genus Echinococcus.
A genus of parasitic tapeworms, the larvae of which, under certain conditions, infect humans, forming large hydatid cysts in the liver or lungs and causing serious or fatal disease.