Where does “ubi” come from?

ubi (Indonesian) comes from Malay ubi, from Classical Malay ubi, from Proto-Malayic hubi, from Proto-Malayo-Chamic hubi, from Proto-Malayo-Sumbawan hubi, from Proto-Malayo-Polynesian qubi — The purple yam, Dioscorea alata.

ubi (Indonesian): yam