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1.
The act of being juvenile; acting annoyingly younger than your age (like you're in high school when you are in your mid-twenties); acting like a douche.
1. Knock off that juvinility right now!
2. Your caring about me negates the juvinility of your behavior.
3. Your juvinility is a poor example to these young adults who are struggling to become mature and productive people.
by Mattimeo February 13, 2008