Yes, staff is a noun, 'staff' is a singular, common, concrete noun; a word for the people who work for a particular company or organization; employees as a group; a word for the set of lines on which music is written; a word for a long stick used for making walking easier on rough terrain; a stick carried by officials on formal occasions; a flagpole.
The word staff is also a verb: staff, staffs, staffing, staffed; a word for the act of providing workers or to serve as a worker.
A musical staff is a series of lines representing different musical notes. There are different types of musical staff (for example a treble or bass staff) but they all serve the same purpose.
You can loosely think of it as a canvas on which notes are placed where the vertical position of notes indicates their pitch and the horizontal pattern (along with tempo and other musical notation) determines their timing.
The noun 'staff' is a standard collective noun for a staff of employees.
The collective noun 'staff' is used for a staff of workers or a staff of employees.
The collective noun 'staff' is used for a staff of workers or a staff of employees.
The collective noun is a staff of servants.
The noun staff is a singular, common, collective noun.
The noun staff is a singular, common, collective noun.
Collective noun
The word "staff" itself is a collective noun: E.g. (American English) "The staff is on break." (British English) "The staff are on break."
Collective noun
The plural form for of the noun chief-of-staff is chiefs-of-staff.
The plural form for of the noun chief-of-staff is chiefs-of-staff.
Staff of teachers