epidemic myalgia vs diaphragmatic pleurisy

epidemic myalgia and diaphragmatic pleurisy both are nouns.

Word	Noun	Adjective	Verb	Adverb
epidemic myalgia	Yes	No	No	No
diaphragmatic pleurisy	Yes	No	No	No

As nouns, epidemic myalgia and diaphragmatic pleurisy are synonyms defined as:

epidemic myalgia and diaphragmatic pleurisy: an acute infectious disease occurring in epidemic form and featuring paroxysms of pain (usually in the chest)

Other synonyms of epidemic myalgia include Bornholm disease, epidemic pleurodynia, myosis.

epidemic myalgia (noun)	diaphragmatic pleurisy (noun)
an acute infectious disease occurring in epidemic form and featuring paroxysms of pain (usually in the chest)	an acute infectious disease occurring in epidemic form and featuring paroxysms of pain (usually in the chest)