资料来源 : Webster's Revised Unabridged Dictionary (1913)

Open \O"pen\, n.
   Open or unobstructed space; clear land, without trees or
   obstructions; open ocean; open water. ``To sail into the
   open.'' --Jowett (Thucyd. ).

         Then we got into the open.               --W. Black.

   {In open}, in full view; without concealment; openly. [Obs.]