keeper

noun11

1. •
   A person charged with guarding or caring for, storing, or maintaining something; a custodian, a guard; sometimes a gamekeeper.

   • And the Lord said unto Cain, Where is Abel thy brother? And he said, I know not: Am I my brother's keeper? — 1611
2. •
   The player charged with guarding a goal or wicket; a goalkeeper or wicketkeeper.
3. •
   (informal) A person or thing worth keeping.

   • "Okay, that's a keeper," Harold said as he netted the 3-pounder and put him on a stringer over the side of the boat. — 1970
4. •
   One who keeps (retains) something.

   • Finders keepers; losers weepers.
5. •
   One who remains or keeps in a place or position.
6. •
   A fruit or vegetable that keeps (remains good) for some time without spoiling.

   • Roxbury Russet: Market and keeper. — 1847
7. •
   A part of a mechanism that catches or retains another part, for example the part of a door lock that fits in the frame and receives the bolt.
8. •
   An offensive play in which the quarterback runs toward the goal with the ball after it is snapped.
9. •
   Synonym of armature (“piece of metal connecting the poles of a magnet to preserve its strength by forming a circuit”).

   • The continuous lines indicate the moments, when the magnet and keeper of equal diameter (10.5mm) act upon each other […] — 1878
10. •
    A thin, flexible tress or tongue of material (e.g. leather) at the end of a crop opposite the handle, which is broad enough to prevent the horse's skin from being marked as it might be by a whip.

    • The all-whalebone crop, braided with gut, pigskin handle, single brown stitched leather keeper, and close[…] — 1912
11. •
    At Eton College, a student who is the captain of a sport or an activity such as drama.