A stockade was an enclosure used to curb prisoner movement.
In 2154, Major J. Hayes told Lieutenant Malcolm Reed that if one of his men had disobeyed orders the way T'Pol disobeyed Captain Archer, he would've thrown them in the stockade. (ENT: "Hatchery")
In 2293, Rura Penthe had no stockade, a fact the commandant made clear to James T. Kirk and Leonard McCoy. (Star Trek VI: The Undiscovered Country)