A word we all know. But I had never looked at its etymology.
decoy
n.
5< Du de kooi, the cage < de, def. art. (akin to THE) + kooi, cage < WGmc *kawia < L cavea, CAGE6
1 a place into which wild ducks, etc. are lured for capture
2 an artificial bird or animal, or sometimes a trained live one, used to lure game to a place where it can be shot
3 a thing or person used to lure or tempt into danger or a trap !a police decoy"
vt., vi.
to lure or be lured into a trap, danger, etc.
—SYN LURE