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• caterpillar
  caterpillar

  noun

  the wormlike larva of a butterfly or a moth.
• Caterpillar
  Caterpillar

  a tractor intended for rough terrain, propelled by two endless belts or tracks that pass over a number of wheels.

caterpillar

¹ American  

[kat-uh-pil-er, kat-er-] / ˈkæt əˌpɪl ər, ˈkæt ər- /

noun

• caterpillars
  plural

1. the wormlike larva of a butterfly or a moth.

2. a person who preys on others; extortioner.

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Caterpillar ² American  

[kat-uh-pil-er, kat-er-] / ˈkæt əˌpɪl ər, ˈkæt ər- /

Trademark.

1. a tractor intended for rough terrain, propelled by two endless belts or tracks that pass over a number of wheels.

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caterpillar ¹ British  

/ ˈkætəˌpɪlə /

noun

1. the wormlike larva of butterflies and moths, having numerous pairs of legs and powerful biting jaws. It may be brightly coloured, hairy, or spiny

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Caterpillar ² British  

/ ˈkætəˌpɪlə /

noun

1. an endless track, driven by sprockets or wheels, used to propel a heavy vehicle and enable it to cross soft or uneven ground

2. a vehicle, such as a tractor, tank, bulldozer, etc, driven by such tracks

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caterpillar Scientific  

/ kăt′ər-pĭl′ər /

1. The wormlike larva of a butterfly or moth. Caterpillars have thirteen body segments, with three pairs of stubby legs on the thorax and several on the abdomen, six eyes on each side of the head, and short antennae. Caterpillars feed mostly on foliage and are usually brightly colored. Many have poisonous spines.

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Other Word Forms

Noun Inflected Forms

• caterpillars
  plural

Etymology

Origin of caterpillar

1400–50; late Middle English catyrpel, probably alteration of an Old North French variant of Old French chatepelose, equivalent to chate cat ( def. ) + pelose hairy (≪ Latin pilōsus; see pilose); -yr probably by association with cater tomcat ( see caterwaul); final -er probably by association with piller despoiler ( see pillage, -er ¹); cf. chenille

Explanation

A caterpillar is a fuzzy, worm-like insect that transforms into a butterfly or a moth. Many caterpillars are striped and colorful. A caterpillar is officially the larva, or immature form, of a flying insect — generally, a butterfly. Because caterpillars are growing rapidly, they tend to eat constantly, and for this reason they're considered pests by gardeners and farmers. The word caterpillar comes from the Old North French caterpilose, literally "shaggy cat," from the Late Latin catta, "cat," and pilosus, "hairy" or "shaggy."

Example Sentences

See Examples For:

caterpillar Caterpillar caterpillars

Butterfly Conservation said was most likely caused by ermine moth caterpillars, which feed inside the webs and "are the definition of a hungry caterpillar".

From BBC ● May 13, 2026

At least in the sampled bottles, it was consistently the caterpillar of a single moth species.

From Science Daily ● Apr. 26, 2026

Trefry likened this awkward time of life to the stage in a butterfly’s development when a caterpillar disappears inside a chrysalis and dissolves into goo before reforming into something entirely new.

From Salon ● Nov. 24, 2025

If you’ve ever glimpsed a caterpillar dangling from a branch by a silk thread, they’re on their way down.

From The Wall Street Journal ● Oct. 31, 2025

Departing from Goedart’s example, she also included eggs, declaring boldly that eggs were the source of every caterpillar despite widespread public belief in spontaneous generation of insects.

From "The Girl Who Drew Butterflies: How Maria Merian's Art Changed Science" by Joyce Sidman

Companies such as Caterpillar and Cummins are pivoting to feed a booming market for once-prosaic machinery.

From The Wall Street Journal ● Aug. 16, 2026

Caterpillar recorded $392 million in expected tariff recoveries in the most recent quarter and said it doesn’t expect to book more in 2026.

From The Wall Street Journal ● Aug. 13, 2026

Caterpillar CAT 1.87%increase; up pointing triangle notched higher profit in the latest quarter as sales jumped, driven by continued demand for its construction equipment, as well as its engines and generators.

From The Wall Street Journal ● Aug. 4, 2026

Upbeat results from other companies including Caterpillar helped power the Dow Jones Industrial Average to its first close above 54000 on Tuesday.

From The Wall Street Journal ● Aug. 4, 2026

Caterpillar tried on a bunch of different hats.

From "Caterpillar Summer" by Gillian McDunn

The meadow was established in 2023 as part of a scheme to encourage people to grow plants that provide food for caterpillars.

From BBC ● Jul. 23, 2026

Julie was raising some caterpillars too, and she cared a lot about them.

From Los Angeles Times ● Jul. 10, 2026

The local authority advised people not to be concerned about the "harmless" white webbing seen in trees in Belle Isle Park, Exeter, caused by an infestation of caterpillars.

From BBC ● May 13, 2026

Butterfly Conservation said was most likely caused by ermine moth caterpillars, which feed inside the webs and "are the definition of a hungry caterpillar".

From BBC ● May 13, 2026

How exactly did the caterpillars change inside their cocoons?

From "The Girl Who Drew Butterflies: How Maria Merian's Art Changed Science" by Joyce Sidman