flatworm

[ flat-wurm ]

noun

any worm of the phylum Platyhelminthes, having bilateral symmetry and a soft, solid, usually flattened body, including the planarians, tapeworms, and trematodes; platyhelminth.

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Origin of flatworm

First recorded in 1895–1900; flat¹ + worm

Words Nearby flatworm

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use flatworm in a sentence

Planarians are cross-eyed flatworms that biology students used to cut into pieces to study regeneration.
A sea slug’s head can crawl around and grow a whole new body | Susan Milius | April 30, 2021 | Science News For Students
In one way, the flatworms “are better” than a sea slug, Yusa says.
A sea slug’s head can crawl around and grow a whole new body | Susan Milius | April 30, 2021 | Science News For Students
In one sense, planarians, the little cross-eyed flatworms that biology students mince up to study regeneration, “are better,” Yusa says.
A sea slug’s detached head can crawl around and grow a whole new body | Susan Milius | March 8, 2021 | Science News
An initiative in Senegal, for example, will reintroduce edible native river prawns that prey on the snails that transmit the parasitic flatworm that causes schistosomiasis.
The fight to stop the next pandemic starts in the jungles of Borneo | Brian Barth | December 2, 2020 | Popular-Science
In the 1950s, an unknown psychology professor at the University of Michigan named James McConnell made headlines—and eventually became something of a celebrity—with a series of experiments on freshwater flatworms called planaria.
Memories Can Be Injected and Survive Amputation and Metamorphosis - Facts So Romantic | Marco Altamirano | October 20, 2020 | Nautilus

Such is seen in the life history of the liver fluke, a flatworm which kills sheep, and in the tapeworm.
A Civic Biology | George William Hunter
A certain fresh-water flatworm has the mouth and pharynx in the middle of the body.
The Organism as a Whole | Jacques Loeb
The parasite that's doing the damage is a flatworm, a trematode called Hepatodirus hominis.
The Lani People | J. F. Bone
If a flatworm be cut in two, the front piece grows out a new tail, the hind piece a new head, and two perfect worms result.
Biology | Edmund Beecher Wilson

British Dictionary definitions for flatworm

flatworm

/ (ˈflætˌwɜːm) /

noun

any parasitic or free-living invertebrate of the phylum Platyhelminthes, including planarians, flukes, and tapeworms, having a flattened body with no circulatory system and only one opening to the intestine

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for flatworm

flatworm

[ flăt′wûrm′ ]

Any of various parasitic and nonparasitic worms of the phylum Platyhelminthes, characteristically having a soft, flat, bilaterally symmetrical body. Flatworms lack a coelom (body cavity), respiratory system, and circulatory system, but are the most primitive invertebrates to have a brain. The evolutionary history of flatworms is uncertain, but they share some basic characteristics with rotifers, nematodes, and a few other invertebrate phyla. Cestodes (tapeworms), planarians, and trematodes (flukes) are flatworms.

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