churchwarden vs church officer

churchwarden and church officer both are nouns.

Word	Noun	Adjective	Verb	Adverb
churchwarden	Yes	No	No	No
church officer	Yes	No	No	No

As nouns, church officer is a hypernym of churchwarden; that is, church officer is a word with a broader meaning than churchwarden:

churchwarden: an officer in the Episcopal church who helps a parish priest with secular matters
church officer: a church official

churchwarden (noun)	church officer (noun)
an officer in the Episcopal church who helps a parish priest with secular matters	a church official