flatworm

[ flat-wurm ]

noun
  1. 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

1
First recorded in 1895–1900; flat1 + worm

Words Nearby flatworm

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use flatworm in a sentence

  • 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 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
  1. 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

[ flătwûrm′ ]


  1. 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.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.