Where does “ev-” come from?

ev- (Hungarian) comes from Hungarian eszik, from Hungarian ész, from Proto-Turkic es — memory; mind.

Ancestry of “ev-”, step by step

Step	Language	Word	Meaning
1	Hungarian	eszik	to eat; third-person plural indicative present...
2	Hungarian	ész	intellect, brains, mind, reason, judgment,...
3	Proto-Turkic	es	memory; mind

ev- — Etymology, Origin & Word History | Etymology Explorer