The Collaborative International Dictionary of English v.0.48:

Keep \Keep\, n.
   1. The act or office of keeping; custody; guard; care; heed;
      charge. --Chaucer.
      [1913 Webster]

            Pan, thou god of shepherds all,
            Which of our tender lambkins takest keep. --Spenser.
      [1913 Webster]

   2. The state of being kept; hence, the resulting condition;
      case; as, to be in good keep.
      [1913 Webster]

   3. The means or provisions by which one is kept; maintenance;
      support; as, the keep of a horse.
      [1913 Webster]

            Grass equal to the keep of seven cows. --Carlyle.
      [1913 Webster]

            I performed some services to the college in return
            for my keep.                          --T. Hughes.
      [1913 Webster]

   4. That which keeps or protects; a stronghold; a fortress; a
      castle; specifically, the strongest and securest part of a
      castle, often used as a place of residence by the lord of
      the castle, especially during a siege; the dungeon. See
      Illust. of Castle.
      [1913 Webster]

            The prison strong,
            Within whose keep the captive knights were laid.
                                                  --Dryden.
      [1913 Webster]

            The lower chambers of those gloomy keeps. --Hallam.
      [1913 Webster]

            I think . . . the keep, or principal part of a
            castle, was so called because the lord and his
            domestic circle kept, abode, or lived there. --M. A.
                                                  Lower.
      [1913 Webster]

   5. That which is kept in charge; a charge. [Obs.]
      [1913 Webster]

            Often he used of his keep
            A sacrifice to bring.                 --Spenser.
      [1913 Webster]

   6. (Mach.) A cap for retaining anything, as a journal box, in
      place.
      [1913 Webster]

   To take keep, to take care; to heed. [Obs.] --Chaucer.
      [1913 Webster]