iron out differences

from The Collaborative International Dictionary of English v.0.48

Iron \I"ron\, v. t. [imp. & p. p. {Ironed}; p. pr. & vb. n.
   {Ironing}.]
   [1913 Webster]
   1. To smooth with an instrument of iron; especially, to
      smooth, as cloth, with a heated flatiron; -- sometimes
      used with out.
      [1913 Webster]

   2. To shackle with irons; to fetter or handcuff. "Ironed like
      a malefactor." --Sir W. Scott.
      [1913 Webster]

   3. To furnish or arm with iron; as, to iron a wagon.

   {iron out differences} resolve differences; settle a dispute.
      [PJC] Ironbark