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

• cipher
• dwarf
• half-pint
• insignificancy
• lightweight
• morsel
• nobody
• nonentity
• nothing
• nullity
• number
• pip-squeak
• pygmy
• pigmy
• shrimp
• snippersnapper
• twerp
• whippersnapper
• zero
• zilch

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

Lice are parasitic insects that spread through close contact and require prompt treatment with medicated shampoos. —Lindsay Curtis, Health, 2 Feb. 2025

Check previous plant additions for mites and insects. —Tom MacCubbin, Orlando Sentinel, 1 Feb. 2025

Increasing air circulation and sunlight penetration also help ward off insects and prevent diseases. —Janet B. Carson, arkansasonline.com, 31 Jan. 2025

Larger trees may simply have more insects to drop frass, which could impact the results if tree sizes weren’t standardized between forest types. —Ethan Freedman, Popular Science, 29 Jan. 2025

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

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