Source : Webster's Revised Unabridged Dictionary (1913)

Slop \Slop\, v. t. [imp. & p. p. {Slopped}; p. pr. & vb. n.
   {Slopping}.]
   1. To cause to overflow, as a liquid, by the motion of the
      vessel containing it; to spill.

   2. To spill liquid upon; to soil with a liquid spilled.

Source : WordNet®

slop
     n : wet feed (especially for pigs) consisting of mostly kitchen
         waste mixed with water or skimmed or sour milk [syn: {slops},
          {swill}, {pigswill}, {pigwash}]
     [also: {slopping}, {slopped}]

slop
     v 1: cause or allow (a liquid substance) to run or flow from a
          container; "spill the milk"; "splatter water" [syn: {spill},
           {splatter}]
     2: walk through mud or mire; "We had to splosh across the wet
        meadow" [syn: {squelch}, {squish}, {splash}, {splosh}, {slosh}]
     3: ladle clumsily; "slop the food onto the plate"
     4: feed pigs [syn: {swill}]
     [also: {slopping}, {slopped}]

slopping
     See {slop}