balsa vs wood

balsa and wood both are nouns.

Word	Noun	Adjective	Verb	Adverb
balsa	Yes	No	No	No
wood	Yes	No	No	No

As nouns, wood is a hypernym of balsa; that is, wood is a word with a broader meaning than balsa:

balsa (noun)	wood (noun)
forest tree of lowland Central America having a strong very light wood; used for making floats and rafts and in crafts	any wind instrument other than the brass instruments
strong lightweight wood of the balsa tree used especially for floats	a golf club with a long shaft used to hit long shots; originally made with a wooden head
	the trees and other plants in a large densely wooded area
	the hard fibrous lignified substance under the bark of trees