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A compelling need to be the last person to speak during an argument or conversation; finishing an argument with a response of immaturity typically consisting of either repeating the last thing you said over and over until the other person stops talking, making whiny/baby noises, or childish name-calling.
Person 1: You're such a tool.

Person 2: I'm not a tool. I work because I have goals for myself and I don't mind working hard to achieve them.

Person 1: You're a tool.

Person 2: You just said that.

Person 1: You're a tool.

Person 2: Think you've got some last word syndrome, buddy, later.

Person 1: *Shouting after you* Whaa, why don't you cry about it?
by rhastings88 November 10, 2013
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