[1] : WordNet (r) 2.0

runoff
     n 1: the occurrence of surplus liquid as water exceeding the
          limit or capacity syn: overflow, overspill
     2: a final election to resolve an earlier election that did not
        produce a winner
see also:
overflow overspill 

[2] : Moby Thesaurus II by Grady Ward, 1.0

59 moby thesaurus words for "runoff":
   bout, by-election, caucus, closed primary, congressional election,
   contest, contested election, decathlon, defluxion, direct primary,
   discharge, double-header, doubles, drain, drainage, effluence,
   efflux, effluxion, effusion, election, event, exhalation, exhaust,
   flowoff, foursome, game, games of chance, general election, go,
   gush, mandatory primary, match, meet, nonpartisan primary,
   open primary, optional primary, outfall, outflow, outflowing,
   outpour, outpouring, partisan election, pentathlon, play, play-off,
   preference primary, presidential election,
   presidential preference primary, presidential primary, primary,
   primary election, race, referendum, runoff election,
   runoff primary, singles, sport, threesome, twosome

Runoff >> R Words
Runoff, definition of term: Runoff
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