What is Kill Spawn?
1.
As opposed to spawn killing (when you repeatedly kill your opponents directly upon their spawn), kill spawning is when one spawns and immediately kills an enemy, out of extraordinary luck and/or crappy respawn-placements.
I was just walking about on Foundry, enjoying my cyber-existance as an Elite, feeling good about the world, and some red guy just spontaneously materialized and kill spawned me. Thank you, Bungie.
See