The Collaborative International Dictionary of English v.0.48:

Mall \Mall\ (m[add]l), n.
   1. A public access area containing a promenade for
      pedestrians; as, to gather near the Washington monument on
      the mall in Washington.
      [PJC]

   2. The paved or grassy strip between two roadways.
      [PJC]

   3. A shopping area with multiple shops and a concourse for
      predominantly or exclusively pedestrian use; in cities the
      concourse is usually a city street which may be
      temporarily or permamently closed to motor vehicles; in
      suburban areas, a mall is often located on a convenient
      highway, may be large, contained in one building or in
      multiple buildings connected by (usually covered)
      walkways. Also called shopping mall
      [PJC]

WordNet (r) 3.0 (2006):

shopping mall
    n 1: mercantile establishment consisting of a carefully
         landscaped complex of shops representing leading
         merchandisers; usually includes restaurants and a
         convenient parking area; a modern version of the
         traditional marketplace; "a good plaza should have a movie
         house"; "they spent their weekends at the local malls"
         [syn: plaza, mall, center, shopping mall, shopping
         center, shopping centre]