water elm vs Ulmus laevis

water elm and Ulmus laevis both are nouns.

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

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

water elm and Ulmus laevis: Eurasian elm closely resembling the American elm; thrives in a moist environment

water elm (noun)	Ulmus laevis (noun)
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
Eurasian elm closely resembling the American elm; thrives in a moist environment