worm, common name for various unrelated invertebrate animals with soft, often long and slender bodies. Members of the phylum Platyhelminthes Platyhelminthes (plăt'ēhĕlmĭn`thēz)
..... Click the link for more information. , or the flatworms, are the most primitive; they are generally small and flat-bodied and include the free-living planarians planarian, common name for several genera of the free-living (turbellarian) flatworms belonging to the order Tricladida, a name that derives from their characteristic three-branched digestive cavities. Most species range from 1-8 in. to about 1 in. in length (.
..... Click the link for more information. (of the class Turbellaria) as well as the parasitic flukes fluke, parasitic flatworm of the trematoda class, related to the tapeworm . Instead of the cilia, external sense organs, and epidermis of the free-living flatworms, adult flukes have sucking disks with which they cling to their hosts and an external cuticle that
..... Click the link for more information. (class Trematoda) and tapeworms tapeworm, name for the parasitic flatworms forming the class Cestoda. All tapeworms spend the adult phase of their lives as parasites in the gut of a vertebrate animal (called the primary host).
..... Click the link for more information. (class Cestoda). The nemertines, or ribbon worms (phylum Nemertinea Nemertinea (nĕmərtĭn`ēə), phylum of elongated, often flattened, marine Worms , sometimes called ribbon worms.
..... Click the link for more information. ), 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 Rotifera, phylum of predominantly free-living, microscopic, aquatic or semiterrestrial pseudocoelomates . Each rotifer has a head bearing a crown of cilia, the corona, at the anterior end; most rotifers feed with the aid of currents generated by the coronal cilia.
..... Click the link for more information. , Gastrotricha, Kinorhyncha Kinorhyncha (kĭn'ərĭng`kə)
..... Click the link for more information. , Nematoda Nematoda (nĕm'ətōd`ə)
..... Click the link for more information. , and Nematomorpha Nematomorpha (nĕm'ətəmôr`fə), small (about 230 species) phylum of pseudocoelomates ; the horsehair worms .
..... Click the link for more information. . 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 hookworm, any of a number of bloodsucking nematodes in the phylum Nematoda , order Strongiloidae that live as parasites in humans and other mammals and attach themselves to the host's intestines by means of hooks.
..... Click the link for more information. . Other parasitic nematodes include Filaria, the cause of filariasis, which may result in elephantiasis elephantiasis (ĕl`əfăntī`əsĭs)
..... Click the link for more information. ; Trichinella, the cause of trichinosis trichinosis (trĭk'ĭnō`sĭs) or trichiniasis
..... Click the link for more information. ; Ascaris, an intestinal parasite of humans, horses, and pigs; the pinworm pinworm, roundworm, Enterobius vermicularis, worldwide in distribution and the most common source of worm infestation of humans in the United States. Children are more commonly infested than adults.
..... Click the link for more information. , a parasite common in children; the Guinea worm, Dracunculus medinensis, now restricted to N sub-Saharan Africa, 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; 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 Annelida (ənĕl`ĭdə) [Lat.
..... Click the link for more information. ) 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 earthworm, terrestrial, cylindrical segmented worm of the class Oligochaeta. There are 2,200 earthworm species, found all over the world except in arid and arctic regions and ranging in size from 1 in. (2.5 cm) to the 11-ft (330-cm) giant worms of the tropics.
..... Click the link for more information. , of the class Oligochaeta, the leech leech, predacious or parasitic annelid worm of the class Hirudinea, characterized by a cylindrical or slightly flattened body with suckers at either end for attaching to prey.
..... Click the link for more information. (class Hirudinea), and the marine annelids of the class Polychaeta. The sea mouse sea mouse, marine worm of the genus Aphrodite with a short, broad, segmented body, found in moderately deep water. The upper, or dorsal, surface of a sea mouse bears 15 pairs of raised scales; the space between the scales and the body surface forms a channel
..... Click the link for more information. , the clam worm, and the feather duster worm belong to the latter group. The shipworm shipworm or teredo (tĕrē`dō)
..... Click the link for more information. 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 caterpillar (kăt`əpĭl'ər, kăt`ər–), common name for the larva of a moth or butterfly .
..... Click the link for more information. ). However, other insect larvae are completely legless, while still others are equipped with six pairs of legs, as in adult insects (see larva larva, independent, immature animal that undergoes a profound change, or metamorphosis, to assume the typical adult form. Larvae occur in almost all of the animal phyla; because most are tiny or microscopic, they are rarely seen.
..... Click the link for more information. ). Insect larvae known as worms include the armyworm armyworm, larva of a moth, Pseudaletia unipuncta, found in North America E of the Rocky Mts. When numerous, armyworms move in hordes, traveling by night and devouring grasses, young grains, and some leguminous crops. The full-grown larva is about 2 in.
..... Click the link for more information. , bagworm bagworm, common name for the larva of small moths of the family Psychidae. The larva spins a silken cocoon as it travels, hence the term bagworm. When fully grown, the bagworm fastens its covering to a twig and pupates within it.
..... Click the link for more information. , cutworm cutworm, name for the larvae of many moths of the family Noctuidae (owlet moths). These larvae, or caterpillars, feed at night on the stems and roots of young plants, often cutting them off near the surface of the ground. They hide in soil by day.
..... Click the link for more information. , and inchworm inchworm, name for the larvae of moths of the family Geometridae, a large, cosmopolitan group with over 1,200 species indigenous to North America. Also called measuring worms, spanworms, and loopers, inchworms lack appendages in the middle portion of their body,
..... Click the link for more information. .
worm
WORM Computing
worm [wərm]
WORM [wərm]
..... Click the link for more information. , or the flatworms, are the most primitive; they are generally small and flat-bodied and include the free-living planarians planarian, common name for several genera of the free-living (turbellarian) flatworms belonging to the order Tricladida, a name that derives from their characteristic three-branched digestive cavities. Most species range from 1-8 in. to about 1 in. in length (.
..... Click the link for more information. (of the class Turbellaria) as well as the parasitic flukes fluke, parasitic flatworm of the trematoda class, related to the tapeworm . Instead of the cilia, external sense organs, and epidermis of the free-living flatworms, adult flukes have sucking disks with which they cling to their hosts and an external cuticle that
..... Click the link for more information. (class Trematoda) and tapeworms tapeworm, name for the parasitic flatworms forming the class Cestoda. All tapeworms spend the adult phase of their lives as parasites in the gut of a vertebrate animal (called the primary host).
..... Click the link for more information. (class Cestoda). The nemertines, or ribbon worms (phylum Nemertinea Nemertinea (nĕmərtĭn`ēə), phylum of elongated, often flattened, marine Worms , sometimes called ribbon worms.
..... Click the link for more information. ), 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 Rotifera, phylum of predominantly free-living, microscopic, aquatic or semiterrestrial pseudocoelomates . Each rotifer has a head bearing a crown of cilia, the corona, at the anterior end; most rotifers feed with the aid of currents generated by the coronal cilia.
..... Click the link for more information. , Gastrotricha, Kinorhyncha Kinorhyncha (kĭn'ərĭng`kə)
..... Click the link for more information. , Nematoda Nematoda (nĕm'ətōd`ə)
..... Click the link for more information. , and Nematomorpha Nematomorpha (nĕm'ətəmôr`fə), small (about 230 species) phylum of pseudocoelomates ; the horsehair worms .
..... Click the link for more information. . 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 hookworm, any of a number of bloodsucking nematodes in the phylum Nematoda , order Strongiloidae that live as parasites in humans and other mammals and attach themselves to the host's intestines by means of hooks.
..... Click the link for more information. . Other parasitic nematodes include Filaria, the cause of filariasis, which may result in elephantiasis elephantiasis (ĕl`əfăntī`əsĭs)
..... Click the link for more information. ; Trichinella, the cause of trichinosis trichinosis (trĭk'ĭnō`sĭs) or trichiniasis
..... Click the link for more information. ; Ascaris, an intestinal parasite of humans, horses, and pigs; the pinworm pinworm, roundworm, Enterobius vermicularis, worldwide in distribution and the most common source of worm infestation of humans in the United States. Children are more commonly infested than adults.
..... Click the link for more information. , a parasite common in children; the Guinea worm, Dracunculus medinensis, now restricted to N sub-Saharan Africa, 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; 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 Annelida (ənĕl`ĭdə) [Lat.
..... Click the link for more information. ) 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 earthworm, terrestrial, cylindrical segmented worm of the class Oligochaeta. There are 2,200 earthworm species, found all over the world except in arid and arctic regions and ranging in size from 1 in. (2.5 cm) to the 11-ft (330-cm) giant worms of the tropics.
..... Click the link for more information. , of the class Oligochaeta, the leech leech, predacious or parasitic annelid worm of the class Hirudinea, characterized by a cylindrical or slightly flattened body with suckers at either end for attaching to prey.
..... Click the link for more information. (class Hirudinea), and the marine annelids of the class Polychaeta. The sea mouse sea mouse, marine worm of the genus Aphrodite with a short, broad, segmented body, found in moderately deep water. The upper, or dorsal, surface of a sea mouse bears 15 pairs of raised scales; the space between the scales and the body surface forms a channel
..... Click the link for more information. , the clam worm, and the feather duster worm belong to the latter group. The shipworm shipworm or teredo (tĕrē`dō)
..... Click the link for more information. 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 caterpillar (kăt`əpĭl'ər, kăt`ər–), common name for the larva of a moth or butterfly .
..... Click the link for more information. ). However, other insect larvae are completely legless, while still others are equipped with six pairs of legs, as in adult insects (see larva larva, independent, immature animal that undergoes a profound change, or metamorphosis, to assume the typical adult form. Larvae occur in almost all of the animal phyla; because most are tiny or microscopic, they are rarely seen.
..... Click the link for more information. ). Insect larvae known as worms include the armyworm armyworm, larva of a moth, Pseudaletia unipuncta, found in North America E of the Rocky Mts. When numerous, armyworms move in hordes, traveling by night and devouring grasses, young grains, and some leguminous crops. The full-grown larva is about 2 in.
..... Click the link for more information. , bagworm bagworm, common name for the larva of small moths of the family Psychidae. The larva spins a silken cocoon as it travels, hence the term bagworm. When fully grown, the bagworm fastens its covering to a twig and pupates within it.
..... Click the link for more information. , cutworm cutworm, name for the larvae of many moths of the family Noctuidae (owlet moths). These larvae, or caterpillars, feed at night on the stems and roots of young plants, often cutting them off near the surface of the ground. They hide in soil by day.
..... Click the link for more information. , and inchworm inchworm, name for the larvae of moths of the family Geometridae, a large, cosmopolitan group with over 1,200 species indigenous to North America. Also called measuring worms, spanworms, and loopers, inchworms lack appendages in the middle portion of their body,
..... Click the link for more information. .
worm
Any of thousands of species of unrelated invertebrate animals that typically have a soft, slender, elongated body with no appendages. The major phyla are Platyhelminthes (flatworms), Annelida (annelids, or segmented worms), Nemertea (ribbon worms), Acanthocephala (spiny-headed worms), and Aschelminthes (nematodes and others). There are several minor phyla. Length ranges from microscopic (e.g., some aschelminths) to more than 100 ft (30 m) (some ribbon worms). Worms are found worldwide on land and in water. They may be parasitic or free-living and are important as soil conditioners, parasites, and a link in the food chain in all ecosystems. See also fluke, pinworm, polychaete, rotifer, tapeworm, tube worm.
worm
(1) A destructive program that replicates itself throughout a single computer or across a network, both wired and wireless. It can do damage by sheer reproduction, consuming internal disk and memory resources within a single computer or by exhausting network bandwidth. It can also deposit a Trojan that turns a computer into a zombie for spam and other malicious purposes. Very often, the terms "worm" and "virus" are used synonymously; however, worm implies an automatic method for reproducing itself in other computers. See virus, logic bomb, smartphone virus, Worm.ExploreZip virus and Morris worm.
(2) A program that moves through a network and deposits information at each node for diagnostic purposes or causes idle computers to share some of the processing workload. See ethical worm.
(3) (WORM) (Write Once Read Many) An optical disc that can be recorded only once. Updating requires destroying the existing data (all 0s made 1s), and writing new data to an unused part of the disk.
There are two kinds of WORM technologies. Ablative large-format (12-14") WORM is the traditional type, which makes a permanent change in the optical material. Continuous composite write (CCW) WORM is a mode in multifunction 5.25" optical (MO) drives that emulates a WORM drive. The data are not permanently changed, but the drive contains firmware that ensures that recorded areas are not rewritten. See optical disc.
 |
| WORM Cartridges |
|---|
| Large-format 12-14" WORM drives have used the ablative technology. Magneto-optic drives have firmware that turns MO media into write-once disks. |
worm
1. any of various invertebrates, esp the annelids (earthworms, etc.), nematodes (roundworms), and flatworms, having a slender elongated body
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 shaft on which a helical groove has been cut, as in a gear arrangement in which such a shaft meshes with a toothed wheel
5. a spiral pipe cooled by air or flowing water, used as a condenser in a still
6. a nontechnical name for lytta
7. Anatomy any wormlike organ, structure, or part, such as the middle lobe of the cerebellum (vermis cerebelli)
8. Computing a program that duplicates itself many times in a network and prevents its destruction. It often carries a logic bomb or virus
WORM Computing
write once read many times: an optical disk that enables users to store data but not change it
worm [wərm]
(computer science)
A computer program that seeks to replicate itself and to spread, with the goal of consuming and exhausting computer resources, thereby causing computing systems to fail.
(design engineering)
A shank having at least one complete tooth (thread) around the pitch surface; the driver of a worm gear.
(invertebrate zoology)
The common name for members of the Annelida.
Any of various elongated, naked, soft-bodied animals resembling an earthworm.
(metallurgy)
Sweat of molten metal which exudes through the crust of solidifying metal in a casting, and is caused by gas evolution.
WORM [wərm]
(computer science)
Pertaining to a storage device, such as an optical disk, that allows the user to record data only once and to read back the data an unlimited number of times. Abbreviation for write-one, read-many.
| 1. | WORM - Write-Once Read-Many | ||
| 2. | (networking, security) | worm - (From "Tapeworm" in John Brunner's
novel "The Shockwave Rider", via XEROX PARC) A program that
propagates itself over a network, reproducing itself as it
goes. Compare virus. Nowadays the term has negative
connotations, as it is assumed that only crackers write
worms. Perhaps the best-known example was the Great Worm. Compare Trojan horse. |
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