Where does “po” come from?

po (Ido) comes from Esperanto po, from Russian ПО, from Old East Slavic по, from Proto-Slavic po, from Proto-Indo-European h₂pó, from Proto-Indo-European h₂epo — from, off, back; off, away; off, from.

po (Ido): for, at the price of, in exchange for; per

Definitions

for, at the price of, in exchange for; per

Ancestry of “po”, step by step

Step	Language	Word	Meaning
1	Esperanto	po	each, apiece, at, @; The name of the Latin-script...
2	Russian	ПО	software
3	Old East Slavic	по	on, along, by
4	Proto-Slavic	po	after; by; at
5	Proto-Indo-European	h₂pó	off, away
6	Proto-Indo-European	h₂epo	from, off, back; off, away; off, from

Every word from Proto-Indo-European h₂epo →Every word from Proto-Indo-European h₂pó →Every word from Proto-Slavic po →