Where does “sordens” come from?

sordens (Latin) comes from Latin sordeō, from Latin sordes, from Latin sordeo, from Proto-Italic swerdēō, from Proto-Indo-European swerd-éh₁-ye-ti, from Proto-Indo-European swerd- — dirty, dark, black.

Definitions

Ancestry of “sordens”, step by step

Step	Language	Word	Meaning
1	Latin	sordeō	to be dirty, filthy or foul
2	Latin	sordes	dirt, filth, squalor; meanness, stinginess,...
3	Latin	sordeo	I am dirty, filthy or foul; I am mean or base; I...
4	Proto-Italic	swerdēō	—
5	Proto-Indo-European	swerd-éh₁-ye-ti	—
6	Proto-Indo-European	swerd-	dirty, dark, black

Every word from Proto-Indo-European swerd- →Every word from Proto-Indo-European swerd-éh₁-ye-ti →Every word from Proto-Italic swerdēō →