Source : Webster's Revised Unabridged Dictionary (1913)

Banister \Ban"is*ter\, n. [Formerly also banjore and banjer;
   corrupted from bandore, through negro slave pronunciation.]
   A stringed musical instrument having a head and neck like the
   guitar, and its body like a tambourine. It has five strings,
   and is played with the fingers and hands.

Source : WordNet®

banister
     n : a railing at the side of a staircase or balcony to prevent
         people from falling [syn: {bannister}, {balustrade}, {balusters},
          {handrail}]