[ in-sekt ]
See synonyms for: insectinsects on

  1. any animal of the class Insecta, comprising small, air-breathing arthropods having the body divided into three parts (head, thorax, and abdomen), and having three pairs of legs and usually two pairs of wings.

  2. any small arthropod, such as a spider, tick, or centipede, having a superficial, general similarity to the insects.: Compare arachnid.

  1. a contemptible or unimportant person.

  1. of, pertaining to, like, or used for or against insects: an insect bite; insect powder.

Origin of insect

First recorded in 1595–1605; from Latin insectum, noun use of neuter of insectus, past participle of insecāre “to incise, cut”; translation of Greek éntomon “insect,” literally, “notched or incised one”; see entomo-;cf. segment

Other words from insect

  • in·sec·ti·val [in-sek-tahy-vuhl], /ˌɪn sɛkˈtaɪ vəl/, adjective
  • non·in·sect, noun

Words Nearby insect Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use insect in a sentence

British Dictionary definitions for insect


/ (ˈɪnsɛkt) /

  1. any small air-breathing arthropod of the class Insecta, having a body divided into head, thorax, and abdomen, three pairs of legs, and (in most species) two pairs of wings. Insects comprise about five sixths of all known animal species, with a total of over one million named species: Related adjective: entomic

  2. (loosely) any similar invertebrate, such as a spider, tick, or centipede

  1. a contemptible, loathsome, or insignificant person

Origin of insect

C17: from Latin insectum (animal that has been) cut into, insect, from insecāre, from in- ² + secāre to cut; translation of Greek entomon insect

Derived forms of insect

  • insectean, insectan or insectile, adjective
  • insect-like, adjective

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for insect


[ ĭnsĕkt′ ]

  1. Any of very numerous, mostly small arthropods of the class Insecta, having six segmented legs in the adult stage and a body divided into three parts (the head, thorax, and abdomen). The head has a pair of antennae and the thorax usually has one or two pairs of wings. Most insects undergo substantial change in form during development from the young to the adult stage. More than 800,000 species are known, most of them beetles. Other insects include flies, bees, ants, grasshoppers, butterflies, cockroaches, aphids, and silverfish. See Notes at biomass bug entomology.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.