Lyonia mariana vs shrub

Lyonia mariana and shrub both are nouns.

Word	Noun	Adjective	Verb	Adverb
Lyonia mariana	Yes	No	No	No
shrub	Yes	No	No	No

As nouns, shrub is a hypernym of Lyonia mariana; that is, shrub is a word with a broader meaning than Lyonia mariana:

Lyonia mariana: deciduous shrub of coastal plain of the eastern United States having nodding pinkish-white flowers; poisonous to stock
shrub: a low woody perennial plant usually having several major stems

Other hypernyms of Lyonia mariana include bush.

Lyonia mariana (noun)	shrub (noun)
deciduous shrub of coastal plain of the eastern United States having nodding pinkish-white flowers; poisonous to stock	a low woody perennial plant usually having several major stems