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Pronunciation: nem'a-to'da

Definition: The roundworms, a large phylum that includes many of the helminths parasitic in humans and a far greater number of plant-parasitic and free-living soil and aquatic nonparasitic species. For practical purposes, the parasitic nematodes may be placed in two groups, based on their adult habitat in the human body: 1) the intestinal roundworms (the genera Ascaris, Trichuris, Ancylostoma, Necator, Strongyloides, Enterobius, and Trichinella); and 2) the filarial roundworms of the blood, lymphatic tissues, and viscera ( the genera Wuchereria, Mansonella, Loa, Onchocerca, and Dracunculus).

[nemat- + G. eidos, form]

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© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review date: Sep 19, 2016.