Source : Webster's Revised Unabridged Dictionary (1913)

Dropping \Drop"ping\, n.
   1. The action of causing to drop or of letting drop; falling.

   2. pl. That which falls in drops; the excrement or dung of
      animals.

   {Dropping bottle}, an instrument used to supply small
      quantities of a fluid to a test tube or other vessel.

   {Dropping fire}, a continued irregular discharge of firearms.
      

   {Dropping tube}, a tube for ejecting any liquid in drops.