of import vs chief

of import is not a noun while chief is a noun.

Word	Noun	Adjective	Verb	Adverb
of import	No	Yes	No	No
chief	Yes	Yes	No	No

of import (noun)	chief (noun)
	a person who is in charge
	a person who exercises control over workers
	the head of a tribe or clan

of import (adjective)	chief (adjective)
of great significance or value	most important element