Xylaria polymorpha vs dead-men's-fingers

Xylaria polymorpha and dead-men's-fingers both are nouns.

Word	Noun	Adjective	Verb	Adverb
Xylaria polymorpha	Yes	No	No	No
dead-men's-fingers	Yes	No	No	No

As nouns, Xylaria polymorpha and dead-men's-fingers are synonyms defined as:

Xylaria polymorpha and dead-men's-fingers: the fruiting bodies of the fungi of the genus Xylaria

Other synonyms of Xylaria polymorpha include dead-man's-fingers.

Xylaria polymorpha (noun)	dead-men's-fingers (noun)
the fruiting bodies of the fungi of the genus Xylaria	the fruiting bodies of the fungi of the genus Xylaria