From The Art and Popular Culture Encyclopedia
In a hierarchy or tree structure of any kind, a superior is an individual or position at a higher level in the hierarchy than another (a "subordinate" or "inferior"), and thus closer to the apex. It is often used in business terminology to refer to people who are supervisors and in the military to people who are higher in the chain of command (Superior Officer). Superiors are given, sometimes supreme, authority over others in the control. When an order is given one must follow that order and obey it or punishment may be issued.
A Religious Superior is the person to whom a cleric is immediately responsible under canon law. For monks it would be the Abbot (or the Abbess for nuns); for Friars it would be the Prior; for diocesan priests, it would be the local Bishop. In religious orders with a hierarchy above the local community, there will also be superiors general and possibly provincial superiors above the local abbot, prior, or mother superior.