The Collaborative International Dictionary of English v.0.48:

Spile \Spile\ (sp[imac]l), n. [Cf. LG. spile, dial. G. speil,
   speiler, D. spijl. [root]170.]
   1. A small plug or wooden pin, used to stop a vent, as in a
      cask.
      [1913 Webster]

   2. A small tube or spout inserted in a tree for conducting
      sap, as from a sugar maple.
      [1913 Webster]

   3. A large stake driven into the ground as a support for some
      superstructure; a pile.
      [1913 Webster]

   4. (Mining) One of the thick laths or poles driven
      horizontally ahead on top of a set of the main timbering
      in advancing a level in loose ground.

   Syn: forepole; spill[2d].
        [RDH]

   Spile hole, a small air hole in a cask; a vent.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Spile \Spile\ (sp[imac]l), v. t.
   To supply with a spile or a spigot; to make a small vent in,
   as a cask.
   [1913 Webster]

WordNet (r) 3.0 (2006):

spile
    n 1: a column of wood or steel or concrete that is driven into
         the ground to provide support for a structure [syn: pile,
         spile, piling, stilt]
    2: a plug used to close a hole in a barrel or flask [syn:
       bung, spile]

Moby Thesaurus II by Grady Ward, 1.0:

57 Moby Thesaurus words for "spile":
   bar, bind, block, block up, blockade, bung, caulk, check valve,
   chink, choke, choke off, choke up, clog, clog up, cock, congest,
   constipate, cork, cover, dam, dam up, faucet, fill, fill up, foul,
   jam, leg, lid, obstipate, obstruct, pack, pale, palisade, peg,
   picket, pile, pin, plug, plug up, sea cock, shank, spigot, spike,
   spill, stake, stanch, stay, stench, stop, stop up, stopgap,
   stopper, stopple, stuff, stuff up, tap, valve