church vs kirk

church and kirk both are nouns.

Word	Noun	Adjective	Verb	Adverb
church	Yes	No	Yes	No
kirk	Yes	No	No	No

As nouns, kirk is a hyponym of church; that is, kirk is a word with a more specific, narrower meaning than church:

Other hyponyms of church include abbey, basilica, cathedral, cathedral, duomo.

church (noun)	kirk (noun)
a service conducted in a house of worship	a Scottish church
a place for public (especially Christian) worship
one of the groups of Christians who have their own beliefs and forms of worship
the body of people who attend or belong to a particular local church

church (verb)	kirk (verb)
perform a special church rite or service for