Where does “filth” come from?

filth (Middle English) comes from Old English fȳlþu, from Proto-West Germanic fūliþu, from Proto-West Germanic fūl, from Proto-Germanic fūlaz, from Proto-Indo-European pū- — rotten, putrid; be rotten; putrid; to rot, swell,...

Ancestry of “filth”, step by step

StepLanguageWordMeaning
1Old Englishfȳlþufilth
2Proto-West Germanicfūliþufoulness, rottenness, filth
3Proto-West Germanicfūlfoul, dirty
4Proto-Germanicfūlazfoul, dirty; rotten
5Proto-Indo-Europeanpū-rotten, putrid; be rotten; putrid; to rot, swell,...

Words derived from “filth”

Every word from Proto-Indo-European pū- →Every word from Proto-Germanic fūlaz →Every word from Proto-West Germanic fūl →