Use a relay to ground a circuit

Can a relay be used to ground a circuit. If yes how would it be wired? I need to ground a 12 volt bulb that is hot with key on and lights up thru a ground when another circuit is powered on. Thanks..Russ

You just connect one of the relay NO contacts to the other bulb connection and the common terminal of the contacts to ground. You then energize the relay coil from the other circuits power.