respiratory disease vs disease

respiratory disease and disease both are nouns.

Word	Noun	Adjective	Verb	Adverb
respiratory disease	Yes	No	No	No
disease	Yes	No	No	No

As nouns, disease is a hypernym of respiratory disease; that is, disease is a word with a broader meaning than respiratory disease:

respiratory disease (noun)	disease (noun)
a disease affecting the respiratory system	an impairment of health or a condition of abnormal functioning