A decoy is something designed to trick or distract, usually by looking like the real thing but serving a different purpose. Hunters use wooden duck decoys floating on a pond to attract real ducks within range. Police sometimes park empty squad cars along highways as decoys, making drivers slow down even though no officer is inside.

In nature, some animals create their own decoys for survival. Certain lizards can drop their tails when attacked; the wiggling tail becomes a decoy that distracts the predator while the lizard escapes. The four-eyed butterflyfish has fake eyespots near its tail, tricking larger fish into attacking the wrong end.

Decoys work because they exploit expectations. In a soccer game, one player might act as a decoy by making a run that draws defenders away, creating space for a teammate to receive the real pass. During World War II, the Allies built entire fake armies with inflatable tanks and dummy planes to deceive German scouts about where the real invasion would happen.

The word can also be a verb: you might decoy your little brother away from your room by suggesting there’s something interesting happening downstairs. Whether it’s a cardboard cutout or an elaborate trick, a decoy succeeds by making someone focus on the wrong thing at exactly the right time.