packer \pack"er\ (p[a^]k"[~e]r), n.
   1. A person whose business is to pack things; especially, one
      who packs food for preservation or for the market; as, a
      pork packer.
      
[1913 Webster]


   2. A ring of packing or a special device to render gas-tight
      and water-tight the space between the tubing and bore of
      an oil well. [U. S.]
      [Webster 1913 Suppl.]