red osier vs cornel

red osier and cornel both are nouns.

Word	Noun	Adjective	Verb	Adverb
red osier	Yes	No	No	No
cornel	Yes	No	No	No

As nouns, cornel is a hypernym of red osier; that is, cornel is a word with a broader meaning than red osier:

red osier: common North American shrub with reddish purple twigs and white flowers
cornel: a tree of shrub of the genus Cornus often having showy bracts resembling flowers

Other hypernyms of red osier include dogwood, dogwood tree.

red osier (noun)	cornel (noun)
Eurasian osier having reddish or purple twigs and bark rich in tannin	a tree of shrub of the genus Cornus often having showy bracts resembling flowers
common North American shrub with reddish purple twigs and white flowers