Ulmus americana vs water elm

Ulmus americana and water elm both are nouns.

Word	Noun	Adjective	Verb	Adverb
Ulmus americana	Yes	No	No	No
water elm	Yes	No	No	No

As nouns, Ulmus americana and water elm are synonyms defined as:

Ulmus americana and water elm: large ornamental tree with graceful gradually spreading branches common in eastern North America

Other synonyms of Ulmus americana include American elm, rock elm, white elm.

Ulmus americana (noun)	water elm (noun)
large ornamental tree with graceful gradually spreading branches common in eastern North America	large ornamental tree with graceful gradually spreading branches common in eastern North America
	Eurasian elm closely resembling the American elm; thrives in a moist environment