patent vs unobstructed

patent is a noun but unobstructed is not a noun.

Word	Noun	Adjective	Verb	Adverb
patent	Yes	Yes	Yes	No
unobstructed	No	Yes	No	No

patent (noun)	unobstructed (noun)
an official document granting a right or privilege
a document granting an inventor sole rights to an invention

patent (adjective)	unobstructed (adjective)
clearly revealed to the mind or the senses or judgment	free from impediment or obstruction or hindrance
(of a bodily tube or passageway) open; affording free passage

patent (verb)	unobstructed (verb)
make open to sight or notice
obtain a patent for
grant rights to; grant a patent for