Term used to voice or show displeasure at the actions of an over-enthusiastic companion that proceeds ahead into the mission without regard for fellow team-mates, almost every time ruining the action or locking the other players out of the scene until reset or the character dies & re-spawns. References the over-enthusiastic meme/battlecry "Leeroy Jenkins!"
Leader: "Ok, we're set to do this, now before we go in--
player: *runs in ahead of all others, attack enemy & gets killed. others wait until player re-spawns*
Leader: "*sigh* Thanks, Leeroy."
by The Horn'd One September 29, 2017
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