If you’ve ever yelled out “Shotgun!” as you’ve approached a car, you already know what this one means. It’s the coveted front passenger seat of a vehicle, next to the driver. But the origin is a little less than lighthearted.
In the Wild West era, the spot next to a stagecoach driver was for the guard who would be armed with a shotgun in order to ward off bandits.
Example
>Mom, Jake got to ride shotgun this morning—it’s my turn!
>OK, let’s get back on the road. Who wants to ride shotgun?