roundworm

n. nematode, type of parasitic worm that infests the intestines of humans and animals

The nematodes or roundworms (Phylum Nematoda from Greek  (nema): "thread" + -ode "like") are one of the most common phyla of animals, with over 80,000 different described species (over 15,000 are parasitic). They are ubiquitous in freshwater, marine, and terrestrial environments, where they often outnumber other animals in both individual and species counts, and are found in locations as diverse as Antarctica and oceanic trenches. Further, there are a great many parasitic forms, including pathogens in most plants, animals, and also in humans.
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Noun
1. infections of the skin or nails caused by fungi and appearing as itching circular patches
(synonym) tinea, ringworm
(hypernym) fungal infection, mycosis
(hyponym) dhobi itch
2. unsegmented worms with elongated rounded body pointed at both ends; mostly free-living but some are parasitic
(synonym) nematode, nematode worm
(hypernym) worm
(hyponym) common roundworm, Ascaris lumbricoides
(member-holonym) Nematoda, phylum Nematoda, Aschelminthes, phylum Aschelminthes

(n.)
A nematoid worm.
  

ASCARIDE