Castanospermum vs Australian chestnut

Castanospermum and Australian chestnut both are nouns.

Word	Noun	Adjective	Verb	Adverb
Castanospermum	Yes	No	No	No
Australian chestnut	Yes	No	No	No

Castanospermum (noun)	Australian chestnut (noun)
a rosid dicot genus of the subfamily Papilionoideae having one species: Moreton Bay chestnut	Australian tree having pinnate leaves and orange-yellow flowers followed by large woody pods containing 3 or 4 seeds that resemble chestnuts; yields dark strong wood