boat vs unregistered

boat is a noun but unregistered is not a noun.

Word	Noun	Adjective	Verb	Adverb
boat	Yes	No	Yes	No
unregistered	No	Yes	No	No

boat (noun)	unregistered (noun)
a small vessel for travel on water
a dish (often boat-shaped) for serving gravy or sauce

boat (adjective)	unregistered (adjective)
	not registered
	(of animals) not recorded with or certified by an official breed association
	(a boat or vessel) not furnished with official documents

boat (verb)	unregistered (verb)
ride in a boat on water