unregistered vs boat

unregistered is not a noun while boat is a noun.

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

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

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

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