Source : Webster's Revised Unabridged Dictionary (1913)

Shillalah \Shil*la"lah\, Shillelah \Shil*le"lah\, n.
   An oaken sapling or cudgel; any cudgel; -- so called from
   Shillelagh, a place in Ireland of that name famous for its
   oaks. [Irish] [Written also {shillaly}, and {shillely}.]