a hinged vertical airfoil mounted at the tail of an aircraft and used to make horizontal course changes
source: WordNet 3.0
(nautical) steering mechanism consisting of a hinged vertical plate mounted at the stern of a vessel
source: WordNet 3.0
A riddle or sieve.
source: Webster 1913
The mechanical appliance by means of which a vessel is guided or steered when in motion. It is a broad and flat blade made of wood or iron, with a long shank, and is fastened in an upright position, usually by one edge, to the sternpost of the vessel in such a way that it can be turned from side to side in the water by means of a tiller, wheel, or other attachment.
source: Webster 1913
In an aircraft, a surface the function of which is to exert a turning moment about an axis of the craft.
