Filth is disgusting dirt. Covered in filth, the filth of the place, wading through filth.
It is much stronger than dirt and always carries disgust. The second sense is obscene material — talking filth, a mind full of filth — which is old-fashioned and mildly comic now. In British slang, the filth is an insulting term for the police. Note filthy, which also works as an intensifier in filthy rich and filthy weather, where it means simply extreme.
1nounfilthDisgusting dirt.
“The flat was covered in filth after the tenants left, with rubbish and rotten food everywhere.”
2nounobsceneObscene material.
“He was accused of writing filth and sold about a million copies.”
filth is dirt or obscenity.
Old English fylth comes from ful, foul, plus the -th ending that makes nouns of adjectives. Foul, filth and defile are the same family, and the vowel change is the regular Germanic pattern that also gives long and length.
Proto-Indo-European
*puH-
Proto-West Germanic
*fūliþu
Old English
fȳlþu
Middle English
filth
English, today
filth
From Middle English filth, from Old English fȳlþu, from Proto-West Germanic fūliþu, equivalent to foul + th.
Etymology from Wiktionary, CC BY-SA