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Definition: worm from Collins English Dictionary


1 any of various invertebrates, esp the annelids (earthworms, etc), nematodes (roundworms), and flatworms, having a slender elongated body. Related adjective: vermicular

2 any of various insect larvae having an elongated body, such as the silkworm and wireworm

3 any of various unrelated animals that resemble annelids, nematodes, etc, such as the glow-worm and shipworm

4 a gnawing or insinuating force or agent that torments or slowly eats away

5 a wretched or spineless person

6 anything that resembles a worm in appearance or movement

7 a shaft on which a helical groove has been cut, as in a gear arrangement in which such a shaft meshes with a toothed wheel

8 a spiral pipe cooled by air or flowing water, used as a condenser in a still

9 a nontechnical name for lytta

10 anatomy any wormlike organ, structure, or part, such as the middle lobe of the cerebellum (vermis cerebelli) Technical name: vermis

11 computing a program that duplicates itself many times in a network and prevents its destruction. It often carries a logic bomb or virus ▷vb

12 to move, act, or cause to move or act with the slow sinuous movement of a worm

13 (foll by in, into, out of, etc) to make (one's way) slowly and stealthily; insinuate (oneself)

14 (tr; often foll by out of or from) to extract (information, a secret, etc) from by persistent questioning

15 (tr) to free from or purge of worms

16 (tr) nautical to wind yarn around (a rope) so as to fill the spaces between the strands and render the surface smooth for parcelling and serving

[Old English wyrm; related to Old Frisian wirm, Old High German wurm, Old Norse ormr, Gothic waurms, Latin vermis, Greek romos woodworm]

› ˈwormer n

› ˈwormˌlike or ˈwormish adj

Summary Article: worm
From The Columbia Encyclopedia

common name for various unrelated invertebrate animals with soft, often long and slender bodies. Members of the phylum Platyhelminthes, or the flatworms, are the most primitive; they are generally small and flat-bodied and include the free-living planarians (of the class Turbellaria) as well as the parasitic flukes (class Trematoda) and tapeworms (class Cestoda). The nemertines, or ribbon worms (phylum Nemertinea), are often colorful marine carnivores with an extensible proboscis. The smallest species are only a fraction of an inch (less than 2.5 cm) long, while giants of the group range up to 90 ft (27 m) and are the longest of all invertebrates. Pseuodcoelomate worms include those in the phyla Rotifera, Gastrotricha, Kinorhyncha, Nematoda, and Nematomorpha. Of these, the largest phylum is the nematodes, which are probably the most numerous multicellular animals. Also called roundworms and threadworms, the nematodes include widespread free-living species as well as parasites, such as the hookworm. Other parasitic nematodes include Filaria, the cause of filariasis, which may result in elephantiasis; Trichinella, the cause of trichinosis; Ascaris, an intestinal parasite of humans, horses, and pigs; the pinworm, a parasite common in children; the Guinea worm, Dracunculus medinensis, which is ingested as a larva in water and slowly emerges when full grown (up to 3 ft/91 cm) through a painful sore in the skin, but as a result of an eradication program is now found only in Chad and Ethiopia; and various other species that are agricultural pests. Like the nematodes, the hairworms, or horsehair worms, are unsegmented, but they are grouped separately in the phylum Nematomorpha. The larvae are parasitic, first in the bodies of aquatic insects and then within grasshoppers or beetles. The adult is about 6 in. (15 cm) long and covered with brown chitin, giving it a stiff appearance; since the worms were frequently found in watering troughs, superstition had it that they developed from horsehairs. The annelid worms (phylum Annelida) have segmented bodies, distinct heads, digestive tubes, circulatory systems, and brains. Appendages on each segment are used for walking or swimming. They include the earthworm, of the class Oligochaeta, the leech (class Hirudinea), and the marine annelids of the class Polychaeta. The sea mouse, the clam worm, and the feather duster worm belong to the latter group. The shipworm is a type of clam. The larvae of many insects are popularly called worms. Moth and butterfly larvae can be distinguished from adult animals called worms by the presence of several pairs of fleshy appendages at the rear end of the body (see caterpillar). However, other insect larvae are completely legless, while still others are equipped with six pairs of legs, as in adult insects (see larva). Insect larvae known as worms include the armyworm, bagworm, cutworm, and inchworm.

The Columbia Encyclopedia, © Columbia University Press 2018

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