red elm vs elm

red elm and elm both are nouns.

Word	Noun	Adjective	Verb	Adverb
red elm	Yes	No	No	No
elm	Yes	No	No	No

As nouns, elm is a hypernym of red elm; that is, elm is a word with a broader meaning than red elm:

red elm: North American elm having rough leaves that are red when opening; yields a hard wood
elm: any of various trees of the genus Ulmus: important timber or shade trees

Other hypernyms of red elm include elm tree.

As nouns, elm is a hypernym of red elm; that is, elm is a word with a broader meaning than red elm:

red elm: autumn-flowering elm of southeastern United States
elm: any of various trees of the genus Ulmus: important timber or shade trees

Other hypernyms of red elm include elm tree.

red elm (noun)	elm (noun)
North American elm having rough leaves that are red when opening; yields a hard wood	any of various trees of the genus Ulmus: important timber or shade trees
autumn-flowering elm of southeastern United States	hard tough wood of an elm tree; used for e.g. implements and furniture