The Collaborative International Dictionary of English v.0.48:

Hustings \Hus"tings\, n. pl. [OE. husting an assembly, coucil,
   AS. h?sting; of Scand. origin; cf. Icel. h?s?ing; h?s home +
   ?ing thing, assembly, meeting; akin to Dan. & Sw. ting, E.
   thing. See House, and Thing.]
   1. A court formerly held in several cities of England;
      specif., a court held in London, before the lord mayor,
      recorder, and sheriffs, to determine certain classes of
      suits for the recovery of lands within the city. In the
      progress of law reform this court has become unimportant.
      --Mozley & W.
      [1913 Webster]

   2. Any one of the temporary courts held for the election of
      members of the British Parliament.
      [1913 Webster]

   3. The platform on which candidates for Parliament formerly
      stood in addressing the electors. [Eng.]
      [1913 Webster]

            When the rotten hustings shake
            In another month to his brazen lies.  --Tennyson.
      [1913 Webster]

WordNet (r) 3.0 (2006):

hustings
    n 1: the activities involved in political campaigning
         (especially speech making)

Bouvier's Law Dictionary, Revised 6th Ed (1856):

HUSTINGS, Engl. law. The name of a court held before the lord mayor and
aldermen of London; it is the principal and supreme court of the city., See
2 Inst. 327; St. Armand, Hist. Essay on the Legisl. Power of England, 75.