Where does “luther” come from?

luther (Middle English) comes from Old English lȳþre, from Proto-Germanic lūþrijaz, from Proto-Indo-European (s)lew- — to sludge, to wash; loose, limp, flabby; limp,...

Ancestry of “luther”, step by step

Step	Language	Word	Meaning
1	Old English	lȳþre	bad, wicked, base, mean, corrupt, wretched
2	Proto-Germanic	lūþrijaz	neglected, dissolute, useless, bad
3	Proto-Indo-European	(s)lew-	to sludge, to wash; loose, limp, flabby; limp,...

Every word from Proto-Indo-European (s)lew- →Every word from Proto-Germanic lūþrijaz →Every word from Old English lȳþre →