epidemic myalgia vs epidemic pleurodynia

epidemic myalgia and epidemic pleurodynia both are nouns.

Word	Noun	Adjective	Verb	Adverb
epidemic myalgia	Yes	No	No	No
epidemic pleurodynia	Yes	No	No	No

As nouns, epidemic myalgia and epidemic pleurodynia are synonyms defined as:

epidemic myalgia and epidemic pleurodynia: 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, diaphragmatic pleurisy, myosis.

epidemic myalgia (noun)	epidemic pleurodynia (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)