spanker spanker /ˈspæŋkər/

noun

1. A fore-and-aft sail set on the aftermost lower mast (usually the mizzenmast) of a vessel  ( spanker )
   a fore-and-aft sail set on the aftermost lower mast (usually the mizzenmast) of a vessel
   
2. A hitter who slaps (usually another person) with an open hand  ( slapper , spanker )
   a hitter who slaps (usually another person) with an open hand
    Someone slapped me on the back and I turned to see who the slapper was
   someone slapped me on the back and I turned to see who the slapper was
    My father was the designated spanker in our family
   my father was the designated spanker in our family