personnel department vs staff office

personnel department and staff office both are nouns.

Word	Noun	Adjective	Verb	Adverb
personnel department	Yes	No	No	No
staff office	Yes	No	No	No

As nouns, personnel department and staff office are synonyms defined as:

personnel department and staff office: the department responsible for hiring and training and placing employees and for setting policies for personnel management

Other synonyms of personnel department include personnel, personnel office.

personnel department (noun)	staff office (noun)
the department responsible for hiring and training and placing employees and for setting policies for personnel management	the department responsible for hiring and training and placing employees and for setting policies for personnel management