- balsa, balsa wood - strong lightweight wood of the balsa tree used especially for floats
--1 is a kind of wood
--1 is a substance of balsa, Ochroma lagopus - balsa, Ochroma lagopus - forest tree of lowland Central America having a strong very light wood; used for making floats and rafts and in crafts
--2 is a kind of angiospermous tree, flowering tree
--2 is a member of Ochroma, genus Ochroma
--2 has substances: balsa, balsa wood