\Re*tract"or\, n.
One who, or that which, retracts. Specifically:
(a) In breech-loading firearms, a device for withdrawing a
    cartridge shell from the barrel.
(b) (Surg.) An instrument for holding apart the edges of a
    wound during amputation.
(c) (Surg.) A bandage to protect the soft parts from injury
    by the saw during amputation.
(d) (Anat. & Zo["o]l.) A muscle serving to draw in any organ
    or part. See Illust. under {Phylactol[ae]mata}.