Where does “राजबंसि” come from?

राजबंसि (Rajbanshi) comes from Rajbanshi राजबंशी, from Sanskrit राजवंशीय — of the royal race.

Ancestry of “राजबंसि”, step by step

Step	Language	Word	Meaning
1	Rajbanshi	राजबंशी	—
2	Sanskrit	राजवंशीय	of the royal race

राजबंसि — Etymology, Origin & Word History | Etymology Explorer