"Caterpillar"
caterpillar
English
"catyrpel" of 1440, derived from French "chatepelose"
(?), meaning "hairy cat" (cf. "pile", "pilose", from
Latin "pilus" = "hair"; "pill", as in either medicine
lozenge or fuzzball, like the hairballs cats regurgitate
up, from Latin "pila" = "ball, originally knot of
hair"). See also pussy willows and catkins, similar
shapes and fuzzinesses associated with the feline.

Or is it from "piller", meaning "pillager/ravager", and
"cate", meaning "food" (root of today's "caterer"), as
caterpillars devour leaves?

I will restore to you the years that the locust
hath eaten, the cankerworm, and the
caterpillar, and the palmerworm, my great
army which I send among you.
-- Joel 2:25