Where does “dʰar-” come from?

dʰar- (Proto-Indo-Aryan) comes from Proto-Indo-Iranian dʰar-, from Proto-Indo-European dʰer- — to support; to hold.

Ancestry of “dʰar-”, step by step

Step	Language	Word	Meaning
1	Proto-Indo-Iranian	dʰar-	to hold, carry; to bear, support
2	Proto-Indo-European	dʰer-	to support; to hold

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