ecclesiastical vs ecclesiastic

ecclesiastical is not a noun while ecclesiastic is a noun.

Word	Noun	Adjective	Verb	Adverb
ecclesiastical	No	Yes	No	No
ecclesiastic	Yes	Yes	No	No

As adjectives, ecclesiastical and ecclesiastic are synonyms defined as:

ecclesiastical and ecclesiastic: of or associated with a church (especially a Christian Church)

ecclesiastical (noun)	ecclesiastic (noun)
	a clergyman or other person in religious orders

ecclesiastical (adjective)	ecclesiastic (adjective)
of or associated with a church (especially a Christian Church)	of or associated with a church (especially a Christian Church)