A duck decoy is a device to capture wild ducks or other species of waterfowl. Decoys had an advantage over hunting ducks with shotguns as the duck meat did not contain lead shot. Consequently, a higher price could be charged for it.
Screens by a duck decoy pipe in a nature reserve near Waardenburg, the Netherlands (2007)
One of the pipes of Hale Duck Decoy (2005)
A decoy is usually a person, device, or event which resembles what an individual or a group might be looking for, but it is only meant to lure them. Decoys have been used for centuries most notably in game hunting, but also in wartime and in the committing or resolving of crimes.
Carved, wooden duck decoys
An inflatable dummy tank modeled after an M4 Sherman