balsa
/ˈbɒlsə/noun
mass noun
1
- （亦作balsa wood）very lightweight timber used chiefly for making models and rafts（主要用于制造模型和木筏的）轻木木材。
2
- the fast-growing tropical American tree from which this timber is obtained轻木。
2.1
- Ochroma lagopus (or pyramidale), family Bombacaceae.拉丁名Ochroma lagopus(或Ochroma pyramidale), 木棉科。
词源
early 17th cent. (denoting a kind of South American raft or fishing boat)： from Spanish， 'raft'.