: 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
insectadjective
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.
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
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The campaign that originally eradicated screwworm relied on what’s known as the sterile insect technique.—
Robert Kelly,
Fortune,
22 Oct. 2026 The inspector later observed multiple spray cans of Skidoo insect killer inside the establishment, which this brand’s label indicates is not for use in a food establishment.—
Joseph Hernandez,
Kansas City Star,
22 Oct. 2026 The goal is to detect and head off an infestation of the invasive insect next year, county officials said.—
Paula Wethington,
CBS News,
20 Oct. 2026 Plants are resistant to deer browsing and experience no serious insect or disease problems.—
Kim Toscano,
Southern Living,
20 Oct. 2026 See All Example Sentences for insect
Word History
Etymology
Latin insectum, from neuter of insectus, past participle of insecare to cut into, from in- + secare to cut — more at saw
: 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.