The Collaborative International Dictionary of English v.0.48:

Footboard \Foot"board`\, n.
   1. A board or narrow platfrom upon which one may stand or
      brace his feet; as:
      (a) The platform for the engineer and fireman of a
          locomotive.
      (b) The foot-rest of a coachman's box.
          [1913 Webster]

   2. A board forming the foot of a bedstead.
      [1913 Webster]

   3. A treadle.
      [1913 Webster]

WordNet (r) 3.0 (2006):

footboard
    n 1: a narrow platform on which to stand or brace the feet
    2: a vertical board or panel forming the foot of a bedstead