What does nematode mean?
A nematode is a simple, unsegmented worm belonging to the phylum Nematoda. This broad group includes tiny free-living organisms that live in soil, freshwater, and marine environments, as well as parasitic species that infect plants, animals, and occasionally humans. Nematodes are generally slender and cylindrical, tapering at both ends, and they move by flexing their bodies rather than by using legs. Some feed on bacteria or other small organisms, while others feed on the tissues of their hosts. The word is especially important in agriculture and medicine: plant-parasitic nematodes can reduce crop yields, and animal-parasitic nematodes can cause disease in livestock or people. Although nematodes are commonly called roundworms, the scientific term is more comprehensive and is preferred when referring to the entire group.
nounA nematode is a simple, unsegmented worm belonging to the phylum Nematoda, including many free-living species as well as parasites of plants and animals. The term is also used more narrowly for parasitic roundworms.
- A simple, unsegmented worm of the phylum Nematoda, including free-living and parasitic species.
"The farmer tested the soil for plant-parasitic nematodes before planting the tomatoes."
"Researchers examined the soil to determine whether nematodes were damaging the wheat roots."
"The laboratory identified a parasitic nematode in samples taken from the patient."
The usual plural form for more than one nematode; the singular is used for an individual worm.
"The scientists counted thousands of nematodes in a small sample of soil."
Some of the most important nematodes are microscopic, helping to shape soil ecosystems and threatening crops, livestock, and humans.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does nematode come from?
The word comes from Greek nēma, meaning “thread” or “yarn,” combined with a form meaning “like” or “resembling.” This reflects the threadlike appearance of many small nematodes. English borrowed the term in the 19th century, and related scientific words such as nematic, nematoid, and nematology developed from the same Greek root.
How nematode is actually used
The term is used in biology, agriculture, veterinary medicine, and medicine. In general writing, it may sound more technical than roundworm, although roundworm is also commonly used for particular parasitic species.
Easily confused with nematode
Nematodes are unsegmented roundworms, whereas annelids, such as earthworms and leeches, have visibly segmented bodies.