black bead vs shrub

black bead and shrub both are nouns.

Word	Noun	Adjective	Verb	Adverb
black bead	Yes	No	No	No
shrub	Yes	No	No	No

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

black bead: erect shrub with small if any spines having racemes of white to yellow flowers followed by curved pointed pods and black shiny seeds; West Indies and Florida
shrub: a low woody perennial plant usually having several major stems

Other hypernyms of black bead include bush.

black bead (noun)	shrub (noun)
erect shrub with small if any spines having racemes of white to yellow flowers followed by curved pointed pods and black shiny seeds; West Indies and Florida	a low woody perennial plant usually having several major stems