(1):
(n.) A cowl-shaped cap, commonly turning with the wind, used to improve the draft of a chimney, ventilating shaft, etc.
(2):
(n.) A wire cap for the smokestack of a locomotive.
(3):
(n.) A vessel carried on a pole between two persons, for conveyance of water.
(4):
(n.) A monk's hood; - usually attached to the gown. The name was also applied to the hood and garment together.