An overly derogatory and condescending way of telling someone that their input in a given conversation is childish and/or uneducated and will not heighten the level of intelligence in the discussion.

Also is used when one is short-tempered and unwilling to deal with more than one person in a heated discussion.
Person 1: What country do you think is the most technologically advanced in the world?

Person 2: Well Japan has to be in the top three - if not the number one most advanced in the world.

Person 3: Somalia's gotta be up there too.

Person 2: Okay, the grown-ups are talking. Just stand over there.
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Husband: I can't believe you cheated on me with my best friend!

Wife: Well, I wasn't thinking straight and he's always there for me.

Husband's best friend: I am around a lot.

Husband: Jesus Christ, the grown-ups are talking! Go the fuck away.
by ScottyV89 July 5, 2010
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