purulent pleurisy vs pleurisy

purulent pleurisy and pleurisy both are nouns.

Word	Noun	Adjective	Verb	Adverb
purulent pleurisy	Yes	No	No	No
pleurisy	Yes	No	No	No

As nouns, pleurisy is a hypernym of purulent pleurisy; that is, pleurisy is a word with a broader meaning than purulent pleurisy:

purulent pleurisy: a collection of pus in the lung cavity
pleurisy: inflammation of the pleura of the lungs (especially the parietal layer)

Other hypernyms of purulent pleurisy include empyema.

purulent pleurisy (noun)	pleurisy (noun)
a collection of pus in the lung cavity	inflammation of the pleura of the lungs (especially the parietal layer)