Where does “замазать” come from?

замазать (Russian) comes from Russian ма́зать, from Proto-Slavic màzati, from Proto-Indo-European meh₂ǵ- — to knead, stroke.

Ancestry of “замазать”, step by step

Step	Language	Word	Meaning
1	Russian	ма́зать	to smear, to daub; to smear, spread; to smear; to...
2	Proto-Slavic	màzati	to oil, to anoint, to smear; to oil, to smear, to...
3	Proto-Indo-European	meh₂ǵ-	to knead, stroke

замазать — Etymology, Origin & Word History | Etymology Explorer