I was enjoying a late morning break in the park on a beautiful day when an equally beautiful butterfly found a nice pollen depot nearby. I wasn't especially close to this butterfly, yet I swear I saw it drop some refuse from its body as it fluttered gracefully from flower to flower. Then I saw it again. Then I google it: "Do butterflies...(poop" is number three on the autofill, go figure).
I couldn't help but record here what I'll call the folk entymology -
As it turns out, yes, butterflies DO poop. The bowel movement of insects, including butterflies, is known as frass. I assume that's a made-up word that combines "fragrance " and "ass" into an optimistic euphemism for excrement.
And the correction -
The etymology of frass is the German "fressen", meaning "to devour".