chief vs of import

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

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

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

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