loader

from WordNet (r) 3.0 (2006)

loader
    n 1: a laborer who loads and unloads vessels in a port [syn:
         {stevedore}, {loader}, {longshoreman}, {docker},
         {dockhand}, {dock worker}, {dockworker}, {dock-walloper},
         {lumper}]
    2: an attendant who loads guns for someone shooting game

from The Collaborative International Dictionary of English v.0.48

Loader \Load"er\, n.
   One who, or that which, loads; a mechanical contrivance for
   loading, as a gun.
   [1913 Webster]