Celtis laevigata vs nettle tree

Celtis laevigata and nettle tree both are nouns.

Word	Noun	Adjective	Verb	Adverb
Celtis laevigata	Yes	No	No	No
nettle tree	Yes	No	No	No

As nouns, nettle tree is a hypernym of Celtis laevigata; that is, nettle tree is a word with a broader meaning than Celtis laevigata:

Celtis laevigata: deciduous shade tree with small black berries; southern United States; yields soft yellowish wood
nettle tree: any of various trees of the genus Celtis having inconspicuous flowers and small berrylike fruits

Other hypernyms of Celtis laevigata include hackberry.

Celtis laevigata (noun)	nettle tree (noun)
deciduous shade tree with small black berries; southern United States; yields soft yellowish wood	any of various trees of the genus Celtis having inconspicuous flowers and small berrylike fruits