brier-wood vs wood

brier-wood and wood both are nouns.

Word	Noun	Adjective	Verb	Adverb
brier-wood	Yes	No	No	No
wood	Yes	No	No	No

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

brier-wood: wood from the hard woody root of the briar Erica arborea; used to make tobacco pipes
wood: the hard fibrous lignified substance under the bark of trees

brier-wood (noun)	wood (noun)
wood from the hard woody root of the briar Erica arborea; used to make tobacco pipes	any wind instrument other than the brass instruments
	a golf club with a long shaft used to hit long shots; originally made with a wooden head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