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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.

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 ?
Sitting down on a block of granite, it was delightful to watch the various insects and birds as they flew past.
We here see in two distant countries a similar relation between plants and insects of the same families, though the species of both are different.
During our stay at Brazil I made a large collection of insects. A few general observations on the comparative importance of the different orders may be interesting to the English entomologist.
I do not here refer to the number of different species, but to that of the individual insects; for on this it is that the most striking character in the entomology of different countries depends.
One day, at Bahia, my attention was drawn by observing many spiders, cockroaches, and other insects, and some lizards, rushing in the greatest agitation across a bare piece of ground.
Certain wasp-like insects, which construct in the corners of the verandahs clay cells for their larvae, are very numerous in the neighbourhood of Rio.
The number of spiders, in proportion to other insects, is here compared with England very much larger; perhaps more so than with any other division of the articulate animals.
This gregarious habit, in so typical a genus as Epeira, among insects, which are so bloodthirsty and solitary that even the two sexes attack each other, is a very singular fact.
Waterhouse for his kindness in naming for me this and many other insects, and giving me much valuable assistance.
'Further on, in the wood down there, they've got no names--however, go on with your list of insects: you're wasting time.'
I shall hereafter have occasion to show that the exotic Lobelia fulgens, in this part of England, is never visited by insects, and consequently, from its peculiar structure, never can set a seed.
In the water-beetle, the structure of its legs, so well adapted for diving, allows it to compete with other aquatic insects, to hunt for its own prey, and to escape serving as prey to other animals.