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Related to Nematoda: Echinodermata


any member of the class nematoda, somewhat resembling common earthworms in appearance; many are found as parasites in humans or other animals. Those most frequently infecting humans include Ascaris lumbricoides (see ascariasis); Enterobius vermicularis (the pinworm; see enterobiasis); the hookworm (see hookworm disease); the filaria (see filariasis); and the trichina (see trichinosis).
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


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 (for example, the genera Ascaris, Trichuris, Ancylostoma, Necator, Strongyloides, Enterobius, and Trichinella); and 2) the filarial roundworms of the blood, lymphatic tissues, and viscera (for example, the genera Wuchereria, Mansonella, Loa, Onchocerca, and Dracunculus).
[nemat- + G. eidos, form]
Farlex Partner Medical Dictionary © Farlex 2012


The roundworms, a large class of the phylum Aschelminthes that includes many of the helminths parasitic in humans. Parasitic nematodes include the intestinal roundworms and the filarial roundworms of the blood, lymphatic tissues, and viscera and some subcutaneous and migratory roundworms.
[nemat- + G. eidos, form]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
References in periodicals archive ?
Aquatic Bugs (F: Pentatomidae) Parasitic mites (F: Hydrachnellidae) Puparium sp (F: Stratiomyiidae) Nematoda Spirina sp.
The small (non-mermithid) Nematoda, all in all 22 taxa, were observed at 13 sites of 20, most abundantly in the bay of Reigi laht and in the lagoon of Kirikulaht connected with each other.
The life history and morphology of Spiroxys contortus (Rudolphi); Nematoda: Spiruridae.
Los artropoda fueron los mas numerosos (n = 22), luego los rotiferos con ocho especies, y con una especie cada una, los filas Rhizopoda, Cnidaria, Nematoda, Tardigrada y Annelida.
First occurrence of a mermithid (Nematoda: Mermithidae) parasitizing a spider (Arachnida: Araneida) in Argentina.
(Nematoda: Dioctophymatoidea) from the stomach of a Nile crocodile, Crocodylus niloticus Laurenti, 1768, in Botswana.
Occurrence of Strongyluris oscari (Nematoda; Heterakidae) in Enyalius bilineatus (Squamata: Leiosaurinae) from the Brazilian Atlantic Forest.