Where does “заквашивать” come from?

заквашивать (Russian) comes from Russian заква́сить, from Russian за́-, from Proto-Slavic za- — for.

заквашивать (Russian): to ferment, to leaven

Definitions

to ferment, to leaven

Ancestry of “заквашивать”, step by step

Step	Language	Word	Meaning
1	Russian	заква́сить	—
2	Russian	за́-	—
3	Proto-Slavic	za-	for

Every word from Proto-Slavic za- →

заквашивать — Etymology, Origin & Word History | Etymology Explorer