flax rust fungus vs Melampsora lini

flax rust fungus and Melampsora lini both are nouns.

Word	Noun	Adjective	Verb	Adverb
flax rust fungus	Yes	No	No	No
Melampsora lini	Yes	No	No	No

As nouns, flax rust fungus and Melampsora lini are synonyms defined as:

Other synonyms of flax rust fungus include flax rust.

flax rust fungus (noun)	Melampsora lini (noun)
fungus causing flax rust	fungus causing flax rust