Insect Definition & Meaning - Merriam-Webster

insect

noun

in·​sect ˈin-ˌsekt How to pronounce insect (audio)
1
a
: any of a class (Insecta) of arthropods (such as bugs or bees) with well-defined head, thorax, and abdomen, only three pairs of legs, and typically one or two pairs of wings
b
: any of numerous small invertebrate animals (such as spiders or centipedes) that are more or less obviously segmented
not used technically
2
: a trivial or contemptible person
insect adjective

Illustration of insect

Illustration of insect
  • 1 labial palpus
  • 2 maxillary palpus
  • 3 simple eye
  • 4 antenna
  • 5 compound eye
  • 6 prothorax
  • 7 tympanum
  • 8 wing
  • 9 ovipositor
  • 10 spiracles
  • 11 abdomen
  • 12 metathorax
  • 13 mesothorax

Did you know?

The bodies of insects have segments, or divisions, so they appear to have a series of notches cut into them. This led the Greek philosopher Aristotle to give insects the name entomon “a thing cut into.” Entomon comes from the prefix en- “in,” combined with the verb temnein “to cut.” Later, when the Romans wanted a word for this kind of creature, they did not simply borrow the Greek word. Instead they translated it with the Latin word insectum, from the verb insecare “to cut into.” Insectum was borrowed into English as insect.

Examples of insect in a Sentence

a swarm of flying insects the magazine's editor in chief was notorious for treating staffers as insects, often not even bothering to learn their names
Recent Examples on the Web Cicadas are some of the loudest insects in the world, according to the Center for Disease Control and Prevention. Solcyré Burga, TIME, 12 Apr. 2024 Cicadas are among the world's loudest insects, some scientists say. The Courier-Journal, 10 Apr. 2024 The lifespans of all organisms range from a few hours or days for insects to hundreds of years for certain whales, sharks and giant tortoises. Jessica Dulong, CNN, 9 Apr. 2024 Afterward, other teams might use this information to study animal reactions based on bird calls or insect sounds. Carlyn Kranking, Smithsonian Magazine, 5 Apr. 2024 Gabby Plante, a 10th-grader at Pioneer, was one of the high schoolers helping students find macroinvertebrates — watershed insects in their larval stages. Sal Pizarro, The Mercury News, 4 Apr. 2024 See Every Star Arriving at the 2024 iHeartRadio Music Awards The Grammy winner’s Instagram caption seems to point not just to her latest manicure but her longtime fascination with insects. Staff Author, Peoplemag, 2 Apr. 2024 The report ranks the destinations based on a barometer that takes the local price of eight tourist essentials into consideration—including coffee, beer, cola, wine, water, sunscreen, insect repellent and a three-course meal. Laura Begley Bloom, Forbes, 30 Mar. 2024 The group is seeking data on pets or animals outside including squirrels, birds, coyotes, lizards and insects. Ella Gonzales, Fort Worth Star-Telegram, 29 Mar. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'insect.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Latin insectum, from neuter of insectus, past participle of insecare to cut into, from in- + secare to cut — more at saw

First Known Use

1601, in the meaning defined at sense 1b

Time Traveler
The first known use of insect was in 1601

Dictionary Entries Near insect

Cite this Entry

“Insect.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/insect. Accessed 17 Apr. 2024.

Kids Definition

insect

noun
in·​sect ˈin-ˌsekt How to pronounce insect (audio)
1
: any of numerous small invertebrate animals (as spiders or centipedes) that are more or less obviously made up of segments
not used technically
2
: any of a class of arthropods (as butterflies, true bugs, two-winged flies, bees, and grasshoppers) with the body clearly divided into a head, thorax, and abdomen, with three pairs of jointed legs, and usually with one or two pairs of wings
Etymology

from Latin insectum "insect," derived from insecare "to cut into," from in- "in" and secare "to cut" — related to dissect, section

Word Origin
The bodies of insects have segments, or divisions. Thus they seem to have a series of notches cut into them. This appearance led the Greek philosopher Aristotle to give insects the name entomon "a thing cut into." Entomon comes from the prefix en- "in," combined with the verb temnein "to cut." Later, when the Romans wanted a word for this kind of creature, they did not simply borrow the Greek word. Instead they translated it into the Latin word insectum, from the verb insecare "to cut into." Insectum was borrowed into English as insect.

Medical Definition

insect

noun
in·​sect ˈin-ˌsekt How to pronounce insect (audio)
: any arthropod of the class Insecta
insect adjective

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