Where does “बाढ़ि” come from?

बाढ़ि (Bhojpuri) comes from Sanskrit वृद्धि, from Sanskrit वृध्, from Proto-Indo-Iranian *Hwardʰ-.

बाढ़ि (Bhojpuri): flood

Definitions

Step	Language	Word	Meaning
1	Sanskrit	वृद्धि	cutting off, abscission; forfeiture, deduction;...
2	Sanskrit	वृध्	—
3	Proto-Indo-Iranian	*Hwardʰ-	—

बाढ़ि — Etymology, Origin & Word History | Etymology Explorer