lady-of-the-night vs shrub

lady-of-the-night and shrub both are nouns.

Word	Noun	Adjective	Verb	Adverb
lady-of-the-night	Yes	No	No	No
shrub	Yes	No	No	No

As nouns, shrub is a hypernym of lady-of-the-night; that is, shrub is a word with a broader meaning than lady-of-the-night:

lady-of-the-night: West Indian shrub with fragrant showy yellowish-white flowers
shrub: a low woody perennial plant usually having several major stems

Other hypernyms of lady-of-the-night include bush.

lady-of-the-night (noun)	shrub (noun)
West Indian shrub with fragrant showy yellowish-white flowers	a low woody perennial plant usually having several major stems