Definitions of darkness:

• noun:   a swarthy complexion
• noun:   having a dark or somber color
• noun:   an unilluminated area

  Example: "He moved off into the darkness"

• noun:   an unenlightened state

  Example: "His lectures dispelled the darkness"

• noun:   absence of light or illumination
• noun:   absence of moral or spiritual values

  Example: "The powers of darkness"