The Collaborative International Dictionary of English v.0.48:

Emptying \Emp"ty*ing\, n.
   1. The act of making empty. --Shak.
      [1913 Webster]

   2. pl. The lees of beer, cider, etc.; yeast. [U.S.]
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Empty \Emp"ty\, v. t. [imp. & p. p. Emptied; p. pr. & vb. n.
   Emptying.]
   To deprive of the contents; to exhaust; to make void or
   destitute; to make vacant; to pour out; to discharge; as, to
   empty a vessel; to empty a well or a cistern.
   [1913 Webster]

         The clouds . . . empty themselves upon the earth.
                                                  --Eccl. xi. 3.
   [1913 Webster]

WordNet (r) 3.0 (2006):

emptying
    n 1: the act of removing the contents of something [syn:
         emptying, voidance, evacuation]

Moby Thesaurus II by Grady Ward, 1.0:

36 Moby Thesaurus words for "emptying":
   aspiration, bleeding, bloodletting, broaching, cleaning out,
   clearance, clearing, cupping, defecation, depletion,
   discharging cargo, drafting, drainage, draining, drawing, egress,
   elimination, evacuation, excretion, exhausting, exhaustion,
   milking, off-loading, phlebotomy, pipetting, pumping, removal,
   siphoning, sucking, suction, tapping, unloading, venesection,
   venting, voidance, voiding