decoy [E17th] A decoy was originally a pond with net-covered channels into which ducks and other wildfowl were enticed to be captured. The wildfowl were attracted by a decoy duck [M17th], a tame duck trained for the purpose or an imitation duck placed on the water. Decoy probably comes from Dutch de kooi ‘the decoy’, the second element of which goes back to Latin cavea *cave.