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

What’s worse, these wood-destroying insects can be hard to spot and are famously challenging to eradicate. —Dan Simms, USA Today, 12 May 2026

Apply insect repellant containing DEET, picaridin, oil of lemon eucalyptus, or IR3535 to bare skin and clothing. —Don Sweeney, Sacbee.com, 11 May 2026

Scientists are linking the decline of insects in part to the overuse and misuse of pesticides, particularly neonicotinoids. —Sheryl De Vore, Chicago Tribune, 11 May 2026

Oaks also produce superior leaf litter with thick, leathery leaves that can take up to three years to break down, thereby sheltering beneficial insects and protecting topsoil. —Luke Miller, Better Homes & Gardens, 11 May 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