Where does “रंगोली” come from?

रंगोली (Hindi) comes from Sanskrit रङ्ग, from Sanskrit रञ्ज्, from Proto-Indo-European *(s)reg-.

Ancestry of “रंगोली”, step by step

Step	Language	Word	Meaning
1	Sanskrit	रङ्ग	colour, paint, dye, hue; the nasal modification...
2	Sanskrit	रञ्ज्	to redden; to dye or color
3	Proto-Indo-European	*(s)reg-	—

रंगोली — Etymology, Origin & Word History | Etymology Explorer