tower mill
The tower mill appeared later than the post mill; it consists of a usually circular, stationary body and a roof that rotates with the help of a fantail.
stock 
Wooden arm to which the sail frame is attached.
sail 
Wooden structure that is attached to the stock; the force of the wind turns it to drive the rotor.
windshaft 
Cylindrical part on which the sails turn; it transmits the movement of the rotor to the windmill machinery.
cap 
Movable upper part of the tower that contains the rotor; it turns to position the sails facing the wind.
tower 
Structure that supports the cap; it houses all the machinery for milling grain.
floor 
Level for accessing the inside of the mill; grain is usually stored at its base.
gallery 
Passageway used to move around the mill floor.
frame 
All the sailbars forming the outline of the sail.
fantail 
Orientation device that is attached to the cap, allowing it to rotate to keep the sails in the direction of the wind.
hemlath 
Thick wooden sailbar on the side of the frame that keeps the narrower sailbars inside the sail.
sailbar 
Elongated piece of wood that forms a sail.
sail cloth 
Cloth attached to a sail that collects wind energy; a large sail cloth is used for weak winds and a small sail cloth for strong winds.