Source : Webster's Revised Unabridged Dictionary (1913)

Leister \Leis"ter\, Lister \Lis"ter\(l[i^]s"t[~e]r), n.
   A spear armed with three or more prongs, for striking fish.
   [Scotland]

Source : WordNet®

leister
     n : a spear with three or more prongs; used for spearing fish
         (especially salmon)