red willow vs red osier

red willow and red osier both are nouns.

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

As nouns, red willow and red osier are synonyms defined as:

red willow and red osier: Eurasian osier having reddish or purple twigs and bark rich in tannin

Other synonyms of red willow include basket willow, purple osier, purple willow, Salix purpurea.

red willow (noun)	red osier (noun)
Eurasian osier having reddish or purple twigs and bark rich in tannin	Eurasian osier having reddish or purple twigs and bark rich in tannin
	common North American shrub with reddish purple twigs and white flowers