a person who assists or gives aid and support; helper.
a person who is subordinate to another in rank, function, etc.; one holding a secondary rank in an office or post: He was assistant to the office manager.
something that aids and supplements another.
a faculty member of a college or university who ranks below an instructor and whose responsibilities usually include grading papers, supervising laboratories, and assisting in teaching.
—adj.
assisting; helpful.
serving in an immediately subordinate position; of secondary rank: an assistant coach.