caterpillaryoudaoicibaDictYouDict[caterpillar 词源字典]
caterpillar: [15] Etymologically, a caterpillar is a ‘hairy cat’. The word comes ultimately from late Latin *catta pilōsa: catta is the source of English cat, while pilōsus ‘hairy’ is a derivative of Latin pilus ‘hair’, from which English gets pile of a carpet. In Old French *catta pilōsa became chatepelose, which passed into English as catyrpel.

The present-day form arose in the 16th century, probably from association with the now obsolete piller ‘plunderer’ (related to English pillage) – caterpillars being regarded, of course, as plunderers of leaves. The notion that caterpillars resemble small furry mammals is also reflected in such names as pussmoth and woolly bear.
=> cat, pile[caterpillar etymology, caterpillar origin, 英语词源]
caterpillar (n.)youdaoicibaDictYouDict
mid-15c., catyrpel, probably altered (by association with Middle English piller "plunderer;" see pillage) from Old North French caterpilose "caterpillar" (Old French chatepelose), literally "shaggy cat" (probably in reference to the "wooly-bear" variety), from Late Latin catta pilosa, from catta "cat" (see cat (n.)) + pilosus "hairy, shaggy, covered with hair," from pilus "hair" (see pile (n.3)). Compare also French chenille "caterpillar," literally "little dog." A Swiss German name for it is teufelskatz "devil's cat." "The caterpillar has in many idioms received the name of other animals" [Kitchin, who cites also Milanese cagnon "little dog," Italian dialectal gattola "little cat," Kentish hop-dog, hop-cat, Portuguese lagarta "lizard." Compare also American English wooly-bear for the hairy variety. An Old English name for it was cawelworm "cole-worm." Caterpillar tractor is from 1908.