hedge thorn vs carissa

hedge thorn and carissa both are nouns.

Word	Noun	Adjective	Verb	Adverb
hedge thorn	Yes	No	No	No
carissa	Yes	No	No	No

As nouns, carissa is a hypernym of hedge thorn; that is, carissa is a word with a broader meaning than hedge thorn:

hedge thorn: South African shrub having forked spines and plumlike fruit; frequently used as hedging
carissa: a shrub of the genus Carissa having fragrant white flowers and plumlike red to purple-black fruits

hedge thorn (noun)	carissa (noun)
South African shrub having forked spines and plumlike fruit; frequently used as hedging	a shrub of the genus Carissa having fragrant white flowers and plumlike red to purple-black fruits