insect

noun

in·​sect ˈin-ˌsekt 

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

• 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.

Synonyms of insect

• dwarf
• cipher
• nobody
• lightweight
• number

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

Climate change is also impacting the state’s most vulnerable species, as a more milder climate leads to a rise in invasive plants and insects. — Stephen Underwood, Hartford Courant, 13 Nov. 2026

So check underneath the piece, inside its drawers, and along the back for telltale holes, which Dill says are all signs of insects in furniture. — Shelby Deering, Southern Living, 12 Nov. 2026

This uses multiple ultrasonic frequencies to repel as wide a range of pests as possible, including spiders, mice and most insects. — Bestreviews, Chicago Tribune, 11 Nov. 2026

Every summer, tourists flock to the bridge at dusk to watch bats pour out from under the bridge for their nightly insect hunt. — Henry Gass, Christian Science Monitor, 10 Nov. 2026

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

Phrases Containing insect

• cochineal insect
• scale insect
• social insect
• spittle insect
• stick insect

Rhymes for insect

• affect
• aspect
• bedecked
• bisect
• collect
• connect
• correct
• deflect
• detect
• direct
• dissect
• effect

Kids Definition

insect

noun

in·​sect ˈin-ˌsekt 

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 

: any arthropod of the class Insecta

insect adjective