rosebush vs sweetbriar

rosebush and sweetbriar both are nouns.

Word	Noun	Adjective	Verb	Adverb
rosebush	Yes	No	No	No
sweetbriar	Yes	No	No	No

As nouns, sweetbriar is a hyponym of rosebush; that is, sweetbriar is a word with a more specific, narrower meaning than rosebush:

rosebush: any of many shrubs of the genus Rosa that bear roses
sweetbriar: Eurasian rose with prickly stems and fragrant leaves and bright pink flowers followed by scarlet hips

rosebush (noun)	sweetbriar (noun)
any of many shrubs of the genus Rosa that bear roses	Eurasian rose with prickly stems and fragrant leaves and bright pink flowers followed by scarlet hips