Splatter

From Halopedia, the Halo wiki

Awarded after hitting and killing an opponent with a vehicle.

The Roadkill (or Splatter in Halo 3) Medal is awarded for hitting and killing an opponent with a vehicle. It is available in all Multiplayer gametypes where a vehicle is available and has a Bungie difficulty rating of 1 (out of 10). It is represented by a five-pointed star with a wheel. After you hit and kill an opponent with a vehicle, a message will appear on your screen that says: "You splattered (player)".