narrow-leaved plantain vs buckthorn

narrow-leaved plantain and buckthorn both are nouns.

Word	Noun	Adjective	Verb	Adverb
narrow-leaved plantain	Yes	No	No	No
buckthorn	Yes	No	No	No

As nouns, narrow-leaved plantain and buckthorn are synonyms defined as:

narrow-leaved plantain and buckthorn: an Old World plantain with long narrow ribbed leaves widely established in temperate regions

Other synonyms of narrow-leaved plantain include English plantain, Plantago lanceolata, ribgrass, ribwort, ripple-grass.

narrow-leaved plantain (noun)	buckthorn (noun)
an Old World plantain with long narrow ribbed leaves widely established in temperate regions	any shrub or small tree of the genus Bumelia
	a shrub or shrubby tree of the genus Rhamnus; fruits are source of yellow dyes or pigments
	an Old World plantain with long narrow ribbed leaves widely established in temperate regions