The story
- Proto-Malayo-Polynesian · derived from*buŋsu
- Tagalog · borrowed frombunso
- English todaybunso
Borrowed from Tagalog bunso, from earlier bungso, an early borrowing from Malay bongsu (“lastborn”), ultimately from Proto-Malayo-Polynesian *buŋsu.
Etymology from Wiktionary, CC BY-SA 4.0.