Where does “ᠵᠢᠳᠠ” come from?

ᠵᠢᠳᠠ (Mongolian) comes from Proto-Mongolic *ǰïda.

Ancestry of “ᠵᠢᠳᠠ”, step by step

Step	Language	Word	Meaning
1	Proto-Mongolic	*ǰïda	—