[1] : The Collaborative International Dictionary of English v.0.48

underrun \un`derrun"\, v. t.
   to run or pass under; especially naut., to pass along and
   under, as a cable, for the purpose of taking it in, or of
   examining it.
   1913 webster

   note: the cable passes over the bows and stern of the boat
         used, while the men haul the boat along by pulling upon
         the cable. --totten.
         1913 webster

   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.

   to underrun a tackle naut., to separate its parts and put
      them in order.
      1913 webster
see also:
to underrun a hose to underrun a tackle 

Underrun >> U Words
Underrun, definition of term: Underrun
underrun_pag1.html

Tackle >> T Words
Tackle, definition of term: Tackle
tackle_pag1.html