Source : Webster's Revised Unabridged Dictionary (1913)

Underrun \Un`der*run"\, v. t.

   {To underrun a hose} (Naut.), to lift it up at one end, then
      walk along shifting one hand after another so that the
      water will run out. Underslung \Un"der*slung`\, Underhung
\Un"der*hung"\, a.
   Of an automobile body, suspended from the springs in such a
   manner that the frame of the chassis is below the axles, the
   object being to lower the center of gravity of the car.