\Tur"ret\, n. [OE. touret, OF. tourette, dim. of tour a
tower, L. turris. See {Tower}.]
1. (Arch.) A little tower, frequently a merely ornamental
   structure at one of the angles of a larger structure.
2. (Anc. Mil.) A movable building, of a square form,
   consisting of ten or even twenty stories and sometimes one
   hundred and twenty cubits high, usually moved on wheels,
   and employed in approaching a fortified place, for
   carrying soldiers, engines, ladders, casting bridges, and
   other necessaries.
3. (Mil.) A revolving tower constructed of thick iron plates,
   within which cannon are mounted. Turrets are used on
   vessels of war and on land.
4. (Railroads) The elevated central portion of the roof of a
   passenger car. Its sides are pierced for light and
   ventilation.
{Turret clock}, a large clock adapted for an elevated
   position, as in the tower of a church.
{Turret head} (Mach.), a vertical cylindrical revolving tool
   holder for bringing different tools into action
   successively in a machine, as in a lathe.
{Turret lathe}, a turning lathe having a turret head.
{Turret ship}, an ironclad war vessel, with low sides, on
   which heavy guns are mounted within one or more iron
   turrets, which may be rotated, so that the guns may be
   made to bear in any required direction.