Abies lowiana vs silver fir

Abies lowiana and silver fir both are nouns.

Word	Noun	Adjective	Verb	Adverb
Abies lowiana	Yes	No	No	No
silver fir	Yes	No	No	No

As nouns, silver fir is a hypernym of Abies lowiana; that is, silver fir is a word with a broader meaning than Abies lowiana:

Abies lowiana: medium to tall fir of central to western United States having a narrow erect crown and soft wood
silver fir: any of various true firs having leaves white or silvery white beneath

Abies lowiana (noun)	silver fir (noun)
medium to tall fir of central to western United States having a narrow erect crown and soft wood	any of various true firs having leaves white or silvery white beneath