A worm is a small, tube-shaped invertebrate with no arms or legs. The worms that hang out in your garden are very helpful, keeping the soil rich and fertile.

Worm can be a contemptuous term for a weak person — and while most worms cause us no harm at all, there are dozens of worms that we'd be better off avoiding. Many worms are parasites, feeding on their host's body. Intestinal worms get into a human or animal's digestive system and make them sick. As a verb, to worm is to move or wriggle with difficulty: "Everyone glares as she worms her way up to the front of the line."

Definitions of worm
  1. noun
    any of numerous relatively small elongated soft-bodied animals especially of the phyla Annelida and Chaetognatha and Nematoda and Nemertea and Platyhelminthes; also many insect larvae
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    helminth, parasitic worm
    worm that is parasitic on the intestines of vertebrates especially roundworms and tapeworms and flukes
    a larva of a woodborer
    acanthocephalan, spiny-headed worm
    any of various worms living parasitically in intestines of vertebrates having a retractile proboscis covered with many hooked spines
    arrowworm, chaetognath
    any worm of the Chaetognatha; transparent marine worm with horizontal lateral and caudal fins and a row of movable curved spines at each side of the mouth
    flatworm, platyhelminth
    parasitic or free-living worms having a flattened body
    nemertean, nemertine, proboscis worm, ribbon worm
    soft unsegmented marine worms that have a threadlike proboscis and the ability to stretch and contract
    beard worm, pogonophoran
    slender animal with tentacles and a tubelike outer covering; lives on the deep ocean bottom
    nematode, nematode worm, roundworm
    unsegmented worms with elongated rounded body pointed at both ends; mostly free-living but some are parasitic
    annelid, annelid worm, segmented worm
    worms with cylindrical bodies segmented both internally and externally
    any arrowworm of the genus Sagitta
    planaria, planarian
    free-swimming mostly freshwater flatworms; popular in laboratory studies for the ability to regenerate lost parts
    fluke, trematode, trematode worm
    parasitic flatworms having external suckers for attaching to a host
    cestode, tapeworm
    ribbonlike flatworms that are parasitic in the intestines of humans and other vertebrates
    Ascaris lumbricoides, common roundworm
    intestinal parasite of humans and pigs
    Ascaridia galli, chicken roundworm
    intestinal parasite of domestic fowl
    Enterobius vermicularis, pinworm, threadworm
    small threadlike worm infesting human intestines and rectum especially in children
    any of various small free-living plant-parasitic roundworms
    Tylenchus tritici, wheat eel, wheat eelworm, wheatworm
    small roundworm parasitic on wheat
    Trichinella spiralis, trichina
    parasitic nematode occurring in the intestines of pigs and rats and human beings and producing larvae that form cysts in skeletal muscles
    parasitic bloodsucking roundworms having hooked mouth parts to fasten to the intestinal wall of human and other hosts
    slender threadlike roundworms living in the blood and tissues of vertebrates; transmitted as larvae by biting insects
    Dracunculus medinensis, Guinea worm
    parasitic roundworm of India and Africa that lives in the abdomen or beneath the skin of humans and other vertebrates
    small primitive marine worm lacking external segmentation and resembling polychaete larvae
    oligochaete, oligochaete worm
    hermaphroditic terrestrial and aquatic annelids having bristles borne singly along the length of the body
    polychaete, polychaete worm, polychete, polychete worm
    chiefly marine annelids possessing both sexes and having paired appendages (parapodia) bearing bristles
    bloodsucker, hirudinean, leech
    carnivorous or bloodsucking aquatic or terrestrial worms typically having a sucker at each end
    type of:
    any animal lacking a backbone or notochord; the term is not used as a scientific classification
  2. noun
    a person who has a nasty or unethical character undeserving of respect
    synonyms: dirt ball, insect, louse
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    type of:
    disagreeable person, unpleasant person
    a person who is not pleasant or agreeable
  3. noun
    screw thread on a gear with the teeth of a worm wheel or rack
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    type of:
    a fastener with a tapered threaded shank and a slotted head
  4. noun
    a software program capable of reproducing itself that can spread from one computer to the next over a network
    worms take advantage of automatic file sending and receiving features found on many computers”
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    type of:
    malevolent program, malware
    a computer program designed to have undesirable or harmful effects
  5. verb
    to move in a twisting or contorted motion, (especially when struggling)
    synonyms: squirm, twist, wrestle, wriggle, writhe
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    make a sudden twisting motion
    type of:
    move so as to change position, perform a nontranslational motion
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