retractor

noun6

1. •
   One who, or that which, retracts.
2. •
   In breech-loading firearms, a device for withdrawing a cartridge shell from the barrel.
3. •
   A surgical instrument used to hold apart the edges of an incision or wound.
4. •
   A bandage to protect soft parts of the body from injury by a surgical saw.
5. •
   A muscle serving to draw in any part.
6. •
   A chess puzzle in which a number of moves are retracted and the solver is challenged to reach an alternate outcome.