nem·​a·​tode | \ ˈne-mə-ˌtōd How to pronounce nematode (audio) \

Definition of nematode

: any of a phylum (Nematoda or Nemata) of elongated cylindrical worms parasitic in animals or plants or free-living in soil or water

called also roundworm

Examples of nematode in a Sentence

Recent Examples on the Web On one farm the faecal nematode-egg count per animal dropped by a quarter. The Economist, "Animal husbandry Nematode parasites kill a lot of sheep," 21 Nov. 2019 Celery Growing Problems Celery’s main enemies are parsley worms, carrot rust flies, and nematodes. The Editors, Good Housekeeping, "How to Grow Your Own Crunchy Celery," 19 Apr. 2017 Drosophila is only the second adult animal to have its brain circuitry mapped at this level of detail, following the nematode C. elegans, back in 1986. Gregory Barber, Wired, "The Most Complete Brain Map Ever Is Here: A Fly's 'Connectome'," 22 Jan. 2020 The latest organisms that researchers have looked to are bacteria in the microbiomes of roundworms that parasitize insects (technically termed enteropathogenic nematodes). Diana Gitig, Ars Technica, "New antibiotic found in bacteria inside a worm inside an insect egg," 20 Nov. 2019 This year alone, Crowther's lab has helped produce the first-ever global distribution maps of soil-dwelling fungal groups and of tiny worms called nematodes, both in Nature, and a global map of earthworm distribution, in this issue of Science. Gabriel Popkin, Science | AAAS, "Catchy findings have propelled this young ecologist to fame—and enraged his critics," 24 Oct. 2019 However, in their free time, some members of the lab search out nematodes in unusual places. Jason Daley, Smithsonian, "California’s Saltiest Lake Is Home to This Arsenic-Resistant, Three-Sexed Worm," 1 Oct. 2019 The California lake is just one of several extreme locales where researchers have spotted nematodes, the phylum all eight worm species belong to. Scottie Andrew, CNN, "Scientists discover a worm that has three sexes and a pouch like a kangaroo's," 27 Sep. 2019 The majority of worms, also known as nematodes, generally break down into males and hermaphrodites. Fox News, "Worm with three sexes that carries its offspring like a kangaroo discovered," 27 Sep. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'nematode.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of nematode

1865, in the meaning defined above

History and Etymology for nematode

ultimately from Greek nēmat-, nēma

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Time Traveler for nematode

Time Traveler

The first known use of nematode was in 1865

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Statistics for nematode

Last Updated

14 Feb 2020

Cite this Entry

“Nematode.” Dictionary, Merriam-Webster, Accessed 24 Feb. 2020.

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More Definitions for nematode


nem·​a·​tode | \ ˈnem-ə-ˌtōd How to pronounce nematode (audio) \

Medical Definition of nematode

 (Entry 1 of 2)

: of or relating to the phylum Nematoda



Medical Definition of nematode (Entry 2 of 2)

: any worm of the phylum Nematoda

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