Definitions of secondary:

• noun:   the defensive football players who line up behind the linemen
• noun:   coil such that current is induced in it by passing a current through the primary coil
• adjective:   not of major importance

  Example: "Played a secondary role in world events"

• adjective:   of second rank or importance or value; not direct or immediate

  Example: "The stone will be hauled to a secondary crusher"

• adjective:   depending on or incidental to what is original or primary

  Example: "A secondary infection"

• adjective:   belonging to a lower class or rank
• adjective:   inferior in rank or status