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any individual of the class Insecta.
insect bites and stings injuries caused by the mouth parts and venom of insects (see also bee sting). Similar conditions are caused by members of the class arachnida, which includes the spiders, scorpions, ticks, and mites; see also spider bite. The most common biting insects are mosquitoes and ants. Bites and stings can be the cause of much discomfort, but there is usually no real danger, unless the individual experiences an allergic or anaphylactic reaction. More commonly, a local infection can develop from scratching the site of the bite. Some insects establish themselves on the skin as parasites, others inject poison, and still others transmit disease. A knowledge of first aid measures for bites and stings can do much to relieve discomfort, prevent infection, and sometimes even save a life.


a. Any of numerous arthropod animals of the class Insecta, having an adult stage characterized by three pairs of legs and a body segmented into head, thorax, and abdomen and usually having one or two pairs of wings. Insects include the flies, crickets, mosquitoes, beetles, butterflies, and bees.
b. Any of various other small, chiefly arthropod animals, such as spiders, centipedes, or ticks, usually having many legs. Not in scientific use.
2. An insignificant or contemptible person.

in′sect′ adj.
in′sec·ti′val (ĭn′sĕk-tī′vəl) adj.
Insectclick for a larger image
Fig. 197 Insect . (a) Vertical section, and (b) front view of insect mouthparts.


any small air-breathing arthropod of the class Insecta, containing organisms that normally in the adult have six legs, three distinct regions to the body (head, thorax and abdomen), one pair of antennae and one or two pairs of wings. Mouthparts are often adapted to the method of feeding, such as biting, piercing and sucking.

Abdominal appendages are absent except in the more primitive groups such as springtails. Most insects have a distinct juvenile stage, a nymph (see EXOPTERYGOTA or a larva (see ENDOPTERYGOTA). These undergo METAMORPHOSIS to form the adult. Insects comprise about five-sixths of all known animal species. The class contains the following groups:

Subclass: APTERYGOTA (wingless)

Orders: Protura

Collembola - springtails

Diplura - japygids

Thysanura - bristletails


Orders: Odonata - dragonflies

Ephemeroptera - mayflies

Orthoptera - grasshoppers

Dermaptera - earwigs

Plecoptera - stoneflies

Isoptera - termites

Embioptera - embiids

Mallophaga - biting lice

Anoplura - sucking lice

Psocoptera - book lice


Hemiptera - bugs

Thysanoptera - thrips


Mecoptera - scorpion flies

Neuroptera - lacewings

Trichoptera - caddisflies

Lepidoptera - butterflies and moths

Diptera - flies

Siphonaptera - fleas

Coleoptera - beetles

Strepsiptera - stylops

Hymenoptera - ants, bees and wasps

The more important insect orders are described under separate headings.


any individual of the class Insecta.

insect bites and stings
injuries caused by the mouth parts and venom of insects and of certain related creatures, known as arachnids—spiders, scorpions, ticks—but popularly classified with insects. Bites and stings can be the cause of much discomfort. Usually there is no real danger, although a local infection can develop from scratching. Some insects, however, establish themselves on the skin as parasites, others inject poison, and still others transmit disease. See also bee sting.
insect growth regulators (IGRs)
substances found naturally in insects which regulate morphogenesis and reproduction; synthetic chemicals with similar activity are used topically and in the environment to control ectoparasites, particularly fleas, as a larvicide and ovicide. Called also juvenoids. See also methoprene, fenoxycarb.
insect larva
the second stage in the standard insect life cycle, the maggot or caterpillar.
insect pupa
stage 3 in the insect life cycle. Inert, dormant stage from which the adult emerges.
insect vector
insects may carry infection mechanically on feet or mouthparts, by passage through the digestive tract but without the insect being infected, or by becoming an intermediate host with some part of the parasite's life cycle taking place in insect tissues.
insect worry
swarms of biting insects cause sufficient worry to interfere with grazing and the animals lose weight.

Patient discussion about insect

Q. an insect bite seems infected and is bleeding... the area under the skin is hard and sore... when pressed it bleeds quite a bit

A. It sounds like you have cellulitis around the area of the bite, and you should see a doctor to decide whether or not this requires antibiotics.

Q. My friend told me that people who allergic to dust are actually allergic to small insect. Is he fooling with me?

A. thanks :)

Q. does mosquito bites considered as an edema a bet with a friend- please help solve an issue an help me win a new I pod :)

A. (don't take the mini i-pod, it sucks). it's true-the mosquito has a number of proteins and materials in his saliva that works as anticoagulants and vasodilators (blood vessel broadening). these causes the bite area to start an immune reaction and one of the consequences is an edema-"an increase of interstitial fluid in any organ", that means fluids are exiting blood system. in this case- not too much...

More discussions about insect
References in classic literature ?
Legrand immediately took the scythe, and cleared with it a circular space, three or four yards in diameter, just beneath the insect, and, having accomplished this, ordered Jupiter to let go the string and come down from the tree.
When you first made this assertion I thought you were jesting; but afterwards I called to mind the peculiar spots on the back of the insect, and admitted to myself that your remark had some little foundation in fact.
Giovanni bent towards the insect, and emitted a deep, long breath.
Hast thou grown so poisonous that this deadly insect perishes by thy breath?
What sort of insects do you rejoice in, where YOU come from?
I don't REJOICE in insects at all,' Alice explained, 'because I'm rather afraid of them--at least the large kinds.
It was the common practice of the dwarf, to catch a number of these insects in his hand, as schoolboys do among us, and let them out suddenly under my nose, on purpose to frighten me, and divert the queen.
These insects were as large as partridges: I took out their stings, found them an inch and a half long, and as sharp as needles.
They passed on, and Eva saw beside each bed a Fairy, who with gentle hands and loving words soothed the suffering insects.
Others learned to heal the wounded insects, whose frail limbs a breeze could shatter, and who, were it not for Fairy hands, would die ere half their happy summer life had gone.
Fortunately, in these regions, there is some sort of compensation for their ravages, since the natives gather these insects in great numbers and greedily eat them.
You don't know what it is to want spiritual tobacco--bad emendations of old texts, or small items about a variety of Aphis Brassicae, with the well-known signature of Philomicron, for the `Twaddler's Magazine;' or a learned treatise on the entomology of the Pentateuch, including all the insects not mentioned, but probably met with by the Israelites in their passage through the desert; with a monograph on the Ant, as treated by Solomon, showing the harmony of the Book of Proverbs with the results of modern research.