What is "insect"

Insect \In"sect\, a.

1. Of or pertaining to an insect or insects.

2. Like an insect; small; mean; ephemeral.

Insect \In"sect\ ([i^]n"s[e^]kt), n. [F. insecte, L. insectum, fr. insectus, p. p. of insecare to cut in. See Section. The name was originally given to certain small animals, whose bodies appear cut in, or almost divided. Cf. Entomology.]

1. (Zo["o]l.) One of the Insecta; esp., one of the Hexapoda. See Insecta.

   Note: The hexapod insects pass through three stages during their growth, viz., the larva, pupa, and imago or adult, but in some of the orders the larva differs little from the imago, except in lacking wings, and the active pupa is very much like the larva, except in having rudiments of wings. In the higher orders, the larva is usually a grub, maggot, or caterpillar, totally unlike the adult, while the pupa is very different from both larva and imago and is inactive, taking no food.

2. (Zo["o]l.) Any air-breathing arthropod, as a spider or scorpion.

3. (Zo["o]l.) Any small crustacean. In a wider sense, the word is often loosely applied to various small invertebrates.

4. Fig.: Any small, trivial, or contemptible person or thing.
   --Thomson.

   Insect powder,a powder used for the extermination of insects; esp., the powdered flowers of certain species of Pyrethrum, a genus now merged in Chrysanthemum. Called also Persian powder.

c.1600, from Latin (animal) insectum "(animal) with a notched or divided body," literally "cut into," from neuter past participle of insectare "to cut into, to cut up," from in- "into" (see in- (2)) + secare "to cut" (see section (n.)). Pliny's loan-translation of Greek entomon "insect" (see entomology), which was Aristotle's term for this class of life, in reference to their "notched" bodies.\n

\nFirst in English in 1601 in Holland's translation of Pliny. Translations of Aristotle's term also form the usual word for "insect" in Welsh (trychfil, from trychu "cut" + mil "animal"), Serbo-Croatian (zareznik, from rezati "cut"), Russian (nasekomoe, from sekat "cut"), etc.

n. An arthropod in the class Insecta, characterized by six legs, up to four wings, and a chitinous exoskeleton.

1. n. small air-breathing arthropod

2. a person who has a nasty or unethical character undeserving of respect [syn: worm, louse, dirt ball]

Insects (from Latin , a calque of Greek [], "cut into sections") are a class of invertebrates within the arthropod phylum that have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs of jointed legs, compound eyes and one pair of antennae. They are the most diverse group of animals on the planet, including more than a million described species and representing more than half of all known living organisms. The number of extant species is estimated at between six and ten million, and potentially represent over 90% of the differing animal life forms on Earth. Insects may be found in nearly all environments, although only a small number of species reside in the oceans, a habitat dominated by another arthropod group, crustaceans.

The life cycles of insects vary but most hatch from eggs. Insect growth is constrained by the inelastic exoskeleton and development involves a series of molts. The immature stages can differ from the adults in structure, habit and habitat, and can include a passive pupal stage in those groups that undergo 4-stage metamorphosis (see holometabolism). Insects that undergo 3-stage metamorphosis lack a pupal stage and adults develop through a series of nymphal stages. The higher level relationship of the Hexapoda is unclear. Fossilized insects of enormous size have been found from the Paleozoic Era, including giant dragonflies with wingspans of 55 to 70 cm (22–28 in). The most diverse insect groups appear to have coevolved with flowering plants.

Adult insects typically move about by walking, flying or sometimes swimming (see below, Locomotion). As it allows for rapid yet stable movement, many insects adopt a tripedal gait in which they walk with their legs touching the ground in alternating triangles. Insects are the only invertebrates to have evolved flight. Many insects spend at least part of their lives under water, with larval adaptations that include gills, and some adult insects are aquatic and have adaptations for swimming. Some species, such as water striders, are capable of walking on the surface of water. Insects are mostly solitary, but some, such as certain bees, ants and termites, are social and live in large, well-organized colonies. Some insects, such as earwigs, show maternal care, guarding their eggs and young. Insects can communicate with each other in a variety of ways. Male moths can sense the pheromones of female moths over great distances. Other species communicate with sounds: crickets stridulate, or rub their wings together, to attract a mate and repel other males. Lampyridae in the beetle order Coleoptera communicate with light.

Humans regard certain insects as pests, and attempt to control them using insecticides and a host of other techniques. Some insects damage crops by feeding on sap, leaves or fruits. A few parasitic species are pathogenic. Some insects perform complex ecological roles; blow-flies, for example, help consume carrion but also spread diseases. Insect pollinators are essential to the life-cycle of many flowering plant species on which most organisms, including humans, are at least partly dependent; without them, the terrestrial portion of the biosphere (including humans) would be devastated. Many other insects are considered ecologically beneficial as predators and a few provide direct economic benefit. Silkworms and bees have been used extensively by humans for the production of silk and honey, respectively. In some cultures, people eat the larvae or adults of certain insects.

Insects are six-legged arthropods of the class Insecta.

Insect or Insects may also refer to:

• Insects (album) by the band Breed 77
• Insects (film), upcoming Czech animated film
• Insects (journal), scientific periodical on entomology
• Insect-class gunboat