nematode

American  

[nem-uh-tohd] / ˈnɛm əˌtoʊd /

noun

1. any unsegmented worm of the phylum Nematoda, having an elongated, cylindrical body; a roundworm.

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adjective

1. pertaining to the Nematoda.

nematode British  

/ ˈnɛməˌtəʊd /

noun

1. Also called: nematode worm.   roundworm.  any unsegmented worm of the phylum (or class) Nematoda, having a tough outer cuticle. The group includes free-living forms and disease-causing parasites, such as the hookworm and filaria

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nematode Scientific  

/ nĕm′ə-tōd′ /

1. Any of several slender, cylindrical worms of the group Nematoda, which some scientists consider to be a class of the aschelminths and others to be a separate phylum. Most nematodes are tiny and live in enormous numbers in water, soil, plants, and animals. They have a simple structure, with a long hollow gut separated from the body wall by a fluid-filled space. Several nematodes, such as pinworm, roundworm, filaria, and hookworm, are parasites on animals and humans and cause disease. One species, Caenorhabditis elegans (usually called C. elegans), was one of the first animals to have its entire genome sequenced and is important in biological research as a model organism.

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Etymology

Origin of nematode

First recorded in 1860–65; nemat- + -ode ¹

Example Sentences

See Examples For:

nematode

The study included experiments in the nematode Caenorhabditis elegans, investigations using human cell cultures, and analysis of extensive clinical datasets.

From Science Daily ● Jun. 11, 2026

The findings, published in PNAS, focus on the nematode Steinernema carpocapsae and come from a collaboration between scientists at Emory University and the University of California, Berkeley.

From Science Daily ● Oct. 15, 2025

The new nematode fossils predate those Cambrian creatures by about 15 million years, says Hughes, a graduate student at Harvard University.

From Science Magazine ● Nov. 19, 2024

Both conducted their research on the nematode worm - C. elegans.

From BBC ● Oct. 7, 2024

Soil samples showed heavy infestations by tiny nematode worms.

From "Silent Spring" by Rachel Carson