Salix amygdaloides vs willow

Salix amygdaloides and willow both are nouns.

Word	Noun	Adjective	Verb	Adverb
Salix amygdaloides	Yes	No	No	No
willow	Yes	No	No	No

As nouns, willow is a hypernym of Salix amygdaloides; that is, willow is a word with a broader meaning than Salix amygdaloides:

Salix amygdaloides: willow of the western United States with leaves like those of peach or almond trees
willow: any of numerous deciduous trees and shrubs of the genus Salix

Other hypernyms of Salix amygdaloides include willow tree.

Salix amygdaloides (noun)	willow (noun)
willow of the western United States with leaves like those of peach or almond trees	a textile machine having a system of revolving spikes for opening and cleaning raw textile fibers
	any of numerous deciduous trees and shrubs of the genus Salix