Where does “μηδείς” come from?

μηδείς (Ancient Greek) comes from Ancient Greek εἷς, from Proto-Hellenic hens, from Proto-Indo-European sḗm, from Proto-Indo-European sem- — together, one.

μηδείς (Ancient Greek): and not one; nobody, naught, good for naught; not...

Definitions

and not one; nobody, naught, good for naught; not...

Ancestry of “μηδείς”, step by step

μηδείς traces back through two separate lines of ancestry.

via Ancient Greek εἷς

Step	Language	Word	Meaning
1	Ancient Greek	εἷς	one
2	Proto-Hellenic	hens	cardinal number 1 Previous: n/a Next: *dúwō;...
3	Proto-Indo-European	sḗm	one
4	Proto-Indo-European	sem-	together, one

via Ancient Greek μηδέ

Step	Language	Word	Meaning
1	Ancient Greek	μηδέ	but not, and not, nor; not even
2	Ancient Greek	δέ	but, and
3	Proto-Indo-European	de	Emphatic or contrastive particle, and, but;...

Every word from Proto-Indo-European sem- →Every word from Proto-Indo-European sḗm →Every word from Proto-Hellenic hens →