cat·er·pil·lar / ˈkatə(r)ˌpilər/ • n. 1. the larva of a butterfly or moth, having a segmented wormlike body with three pairs of true legs and several pairs of leglike appendages. ∎  (in general use) any similar larva of various insects, esp. sawflies.2. (also caterpillar track or tread) trademark an articulated steel band passing around the wheels of a vehicle for travel on rough ground. ∎  a vehicle with such tracks.ORIGIN: late Middle English: perhaps from a variant of Old French chatepelose, literally ‘hairy cat,’ influenced by obsolete piller ‘ravager.’ The association with “cat”is found in other languages, e.g., Swiss German Teufelskatz (literally ‘devil's cat’), Lombard gatta (literally ‘cat’). Compare with French chaton, English catkin, resembling hairy caterpillars.

caterpillar XV. The earliest recorded form, catyrpel, is prob. — AN. var. of OF. chatepelose ‘hairy cat’; assoc. in XVI with †piller ravager, plunderer (see PILLAGE), prob. brought about the extended form in -piller, -pillar.

caterpillar Larval stage of Lepidoptera, although sometimes the term is also applied to larval Symphyta (sawflies).

caterpillar Worm-like larva of a butterfly or moth; it has a segmented body, short antennae, simple eyes, three pairs of true legs and chewing mouthparts. Nearly all caterpillars feed voraciously on plants and are serious crop pests.