PIE*dhengh「覆う」から。dungの意味は、古ゲルマン時代に人々が冬に暖を取るために地下室の上に糞を敷いたことに由来する。
The whole body of journeymen tailors is divided into two classes, denominated Flints and Dungs: the former work by the day and receive all equal wages; the latter work generally by the piece [1824].Dung beetle attested by 1630s. In colloquial American English, tumble-bug. An Old English word for it was tordwifel "turd weevil."