psychopathology vs mental disturbance

psychopathology and mental disturbance both are nouns.

Word	Noun	Adjective	Verb	Adverb
psychopathology	Yes	No	No	No
mental disturbance	Yes	No	No	No

psychopathology (noun)	mental disturbance (noun)
the branch of medicine dealing with the diagnosis and treatment of mental disorders	(psychiatry) a psychological disorder of thought or emotion; a more neutral term than mental illness
the branch of psychology concerned with abnormal behavior