The Collaborative International Dictionary of English v.0.48:

Stockade \Stock*ade"\, n. [F. estacade stockade, boom (confused
   in French with estocade; see 1st Stoccado); fr. It.
   steccata a palisade (influenced by OF. estach, estaque, a
   stake, post), or from Sp. estacada a palisade; both of German
   origin, and akin to E. stake, stick; cf. G. stecken stick,
   OHG. steccho. See Stake, n., Stick, n. & v. t., and cf.
   Estacade, Stacket.]
   1. (Mil.) A line of stout posts or timbers set firmly in the
      earth in contact with each other (and usually with
      loopholes) to form a barrier, or defensive fortification.
      [Written also stoccade.]
      [1913 Webster]

   2. An inclosure, or pen, made with posts and stakes.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Stockade \Stock*ade"\, v. t. [imp. & p. p. Stockaded; p. pr. &
   vb. n. Stockading.]
   To surround, fortify, or protect with a stockade.
   [1913 Webster]

WordNet (r) 3.0 (2006):

stockade
    n 1: fortification consisting of a fence made of a line of stout
         posts set firmly for defense
    2: a penal camp where political prisoners or prisoners of war
       are confined (usually under harsh conditions) [syn:
       concentration camp, stockade]
    v 1: surround with a stockade in order to fortify