Source : Webster's Revised Unabridged Dictionary (1913)

Scupper \Scup"per\, n. [OF. escopir, escupir, to spit, perhaps
   for escospir, L. ex + conspuere to spit upon; pref. con- +
   spuere to spit. Cf. {Spit}, v.] (Naut.)
   An opening cut through the waterway and bulwarks of a ship,
   so that water falling on deck may flow overboard; -- called
   also {scupper hole}.