green dragon vs dragon arum

green dragon and dragon arum both are nouns.

Word	Noun	Adjective	Verb	Adverb
green dragon	Yes	No	No	No
dragon arum	Yes	No	No	No

As nouns, green dragon and dragon arum are synonyms defined as:

Other synonyms of green dragon include Dracunculus vulgaris.

green dragon (noun)	dragon arum (noun)
early spring-flowering plant of eastern North America resembling the related jack-in-the-pulpit but having digitate leaves, slender greenish yellow spathe and elongated spadix	European arum resembling the cuckoopint
European arum resembling the cuckoopint