From Wiktionary, the free dictionary
A partial reduplication of *ḇuku. The root is likely borrowed from Ternate; compare Ternate bukubuku (“knee”).
ḇuḇuku
- a joint (knee, elbow, etc.)
- a node (in bamboo, etc.)
- Leontine Visser, Clemens Voorhoeve (1987) Sahu-Indonesian-English Dictionary, Brill, page 21 (as 'bu'buku)