chief vs administrator

chief and administrator both are nouns.

Word	Noun	Adjective	Verb	Adverb
chief	Yes	Yes	No	No
administrator	Yes	No	No	No

As nouns, administrator is a hyponym of chief; that is, administrator is a word with a more specific, narrower meaning than chief:

chief (noun)	administrator (noun)
a person who is in charge	someone who administers a business
a person who exercises control over workers	the party appointed by a probate court to distribute the estate of someone who dies without a will or without naming an executor
the head of a tribe or clan	someone who manages a government agency or department

chief (adjective)	administrator (adjective)
most important element