genus Chordospartium vs weeping tree broom

genus Chordospartium and weeping tree broom both are nouns.

Word	Noun	Adjective	Verb	Adverb
genus Chordospartium	Yes	No	No	No
weeping tree broom	Yes	No	No	No

genus Chordospartium (noun)	weeping tree broom (noun)
2 species of small New Zealand trees: weeping tree broom; endangered	small shrubby tree of New Zealand having weeping branches and racemes of white to violet flowers followed by woolly indehiscent two-seeded pods