Source : Webster's Revised Unabridged Dictionary (1913)

Keeper \Keep"er\, n.
   1. One who, or that which, keeps; one who, or that which,
      holds or has possession of anything.

   2. One who retains in custody; one who has the care of a
      prison and the charge of prisoners.

   3. One who has the care, custody, or superintendence of
      anything; as, the keeper of a park, a pound, of sheep, of
      a gate, etc.; the keeper of attached property; hence, one
      who saves from harm; a defender; a preserver.

            The Lord is thy keeper.               --Ps. cxxi. 6.

   4. One who remains or keeps in a place or position.

            Discreet; chaste; keepers at home.    --Titus ii. 5.

   5. A ring, strap, clamp, or any device for holding an object
      in place; as:
      (a) The box on a door jamb into which the bolt of a lock
          protrudes, when shot.
      (b) A ring serving to keep another ring on the finger.
      (c) A loop near the buckle of a strap to receive the end
          of the strap.

   6. A fruit that keeps well; as, the Roxbury Russet is a good
      keeper. -- Downing.

   {Keeper of the forest} (O. Eng. Law), an officer who had the
      principal government of all things relating to the forest.
      

   {Keeper of the great seal}, a high officer of state, who has
      custody of the great seal. The office is now united with
      that of lord chancellor. [Eng.]

   {Keeper of the King's conscience}, the lord chancellor; -- a
      name given when the chancellor was an ecclesiastic. [Eng.]
      

   {Keeper of the privy seal} (styled also lord privy seal), a
      high officer of state, through whose hands pass all
      charters, pardons, etc., before they come to the great
      seal. He is a privy councillor, and was formerly called
      {clerk of the privy seal}. [Eng.]

   {Keeper of a magnet}, a piece of iron which connects the two
      poles, for the purpose of keeping the magnetic power
      undiminished; an armature.

Source : WordNet®

keeper
     n 1: someone in charge of other people; "am I my brother's
          keeper?"
     2: one having charge of buildings or grounds or animals [syn: {custodian},
         {steward}]