European hornbeam vs hornbeam

European hornbeam and hornbeam both are nouns.

Word	Noun	Adjective	Verb	Adverb
European hornbeam	Yes	No	No	No
hornbeam	Yes	No	No	No

As nouns, hornbeam is a hypernym of European hornbeam; that is, hornbeam is a word with a broader meaning than European hornbeam:

European hornbeam: medium-sized Old World tree with smooth grey bark and leaves like beech that turn yellow-orange in autumn
hornbeam: any of several trees or shrubs of the genus Carpinus

European hornbeam (noun)	hornbeam (noun)
medium-sized Old World tree with smooth grey bark and leaves like beech that turn yellow-orange in autumn	any of several trees or shrubs of the genus Carpinus