willow vs genus Salix

willow and genus Salix both are nouns.

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

willow (noun)	genus Salix (noun)
a textile machine having a system of revolving spikes for opening and cleaning raw textile fibers	a large and widespread genus varying in size from small shrubs to large trees: willows
any of numerous deciduous trees and shrubs of the genus Salix