Where does “Av” come from?

Av comes from Hebrew אָב, derived from Akkadian 𒉈, which traces to Proto-Semitic ʾiš-.

Ancestry of “Av”, step by step

Step	Language	Word	Meaning
1	Hebrew	אָב	chief; father; father; ancestor, forefather
2	Akkadian	𒉈	Ab, fifth month of the year; fire
3	Sumerian	𒉈	to bring, carry; to burn; fire

Av — Etymology, Origin & Word History | Etymology Explorer