The Collaborative International Dictionary of English v.0.48:

Story \Sto"ry\, n.; pl. Stories. [OF. estor['e], estor['e]e,
   built, erected, p. p. of estorer to build, restore, to store.
   See Store, v. t.]
   A set of rooms on the same floor or level; a floor, or the
   space between two floors. Also, a horizontal division of a
   building's exterior considered architecturally, which need
   not correspond exactly with the stories within. [Written also
   storey.]
   [1913 Webster]

   Note: A story comprehends the distance from one floor to
         another; as, a story of nine or ten feet elevation. The
         spaces between floors are numbered in order, from below
         upward; as, the lower, second, or third story; a house
         of one story, of two stories, of five stories.
         [1913 Webster]

   Story post (Arch.), a vertical post used to support a floor
      or superincumbent wall.
      [1913 Webster]