complication vs disease

complication and disease both are nouns.

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

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

complication: any disease or disorder that occurs during the course of (or because of) another disease
disease: an impairment of health or a condition of abnormal functioning

complication (noun)	disease (noun)
the act or process of complicating	an impairment of health or a condition of abnormal functioning
puzzling complexity
a development that complicates a situation
a situation or condition that is complex or confused
any disease or disorder that occurs during the course of (or because of) another disease