The Collaborative International Dictionary of English v.0.48:

Settling \Set"tling\, n.
   1. The act of one who, or that which, settles; the act of
      establishing one's self, of colonizing, subsiding,
      adjusting, etc.
      [1913 Webster]

   2. pl. That which settles at the bottom of a liquid; lees;
      dregs; sediment. --Milton.
      [1913 Webster]

   Settling day, a day for settling accounts, as in the stock
      market.
      [1913 Webster]