silk oak vs grevillea

silk oak and grevillea both are nouns.

Word	Noun	Adjective	Verb	Adverb
silk oak	Yes	No	No	No
grevillea	Yes	No	No	No

As nouns, grevillea is a hypernym of silk oak; that is, grevillea is a word with a broader meaning than silk oak:

silk oak: any of several Australian timber trees having usually fernlike foliage and mottled wood used in cabinetry and veneering
grevillea: any shrub or tree of the genus Grevillea

silk oak (noun)	grevillea (noun)
any of several Australian timber trees having usually fernlike foliage and mottled wood used in cabinetry and veneering	any shrub or tree of the genus Grevillea