One who has trouble organising his own life, or sticking to a social decision because he may be judged silently by others about it.
"Are you coming or not? Don't be a Dean about"
I want to get somewhere in life, where is Dean?
"you are sooo Dean, you rock!"
girl 2: oh yeah, thats dean, of course hed look cute ;)
"Theres no way that just happened. That was so DEAN."
"This weekend were so getting DEAN"