The act of slamming one's genitals at speeds in excess of 45 MPH. One person must drive down a highway, or any road that has the correct speed limit. They must drive on the far right or the far left lane of the road.

Person #2 must be on the far left or far right of the car, putting themselves right next to the shoulder of the road. They must then pull out their genitals and stick their dick out of the window.

Person #3 does not have to be a willing participant. They must only be a bystander on the shoulder of the highway.

If all 3 people are present and doing their jobs, then Person #1 will accelerate above 45 MPH whilst going past Person #3, who will be slammed with Person #2's dick and what would feel like lightspeed.

Note: Person #2's dick must be longer that the side mirrors of the car, or else it becomes a Lightspeed Side-mirror-slam. For this reason, black men are ideal for Person #2, and Asian men are highly discouraged.
I heard that Joe got Lightspeed Dickslammed the other day while walking home from the mall.

Serves him right. Why was he walking from the mall?
by VI6VI August 5, 2011
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