staffer vs staff member

staffer and staff member both are nouns.

Word	Noun	Adjective	Verb	Adverb
staffer	Yes	No	No	No
staff member	Yes	No	No	No

As nouns, staffer and staff member are synonyms defined as:

staffer and staff member: an employee who is a member of a staff of workers (especially a member of the staff that works for the President of the United States)

staffer (noun)	staff member (noun)
an employee who is a member of a staff of workers (especially a member of the staff that works for the President of the United States)	an employee who is a member of a staff of workers (especially a member of the staff that works for the President of the United States)