Where does “*sleupan” come from?

*sleupan (Proto-West Germanic) comes from Proto-Germanic sleupaną, from Proto-Indo-European slewb(ʰ)- — to slip, glide.

Ancestry of “*sleupan”, step by step

Step	Language	Word	Meaning
1	Proto-Germanic	sleupaną	To creep, slink, sneak, slip
2	Proto-Indo-European	slewb(ʰ)-	to slip, glide

*sleupan — Etymology, Origin & Word History | Etymology Explorer