encopresis vs mental disorder

encopresis and mental disorder both are nouns.

Word	Noun	Adjective	Verb	Adverb
encopresis	Yes	No	No	No
mental disorder	Yes	No	No	No

As nouns, mental disorder is a hypernym of encopresis; that is, mental disorder is a word with a broader meaning than encopresis:

encopresis: involuntary defecation not attributable to physical defects or illness
mental disorder: (psychiatry) a psychological disorder of thought or emotion; a more neutral term than mental illness

Other hypernyms of encopresis include disturbance, folie, mental disturbance, psychological disorder.

encopresis (noun)	mental disorder (noun)
involuntary defecation not attributable to physical defects or illness	(psychiatry) a psychological disorder of thought or emotion; a more neutral term than mental illness