The Collaborative International Dictionary of English v.0.48:

Presser \Press"er\, n.
   One who, or that which, presses.
   [1913 Webster]

   Presser bar, or Presser wheel (Knitting machine), a bar
      or wheel which closes the barbs of the needles to enable
      the loops of the yarn to pass over them.

   Presser foot, the part of a sewing machine which rests on
      the cloth and presses it down upon the table of the
      machine.
      [1913 Webster]