To leave without saying goodbye, esp. while generally being emo.
Wait, when did Rob leave?
I have no idea, he just emo left.
Hey, next time tell us when you're going... don't just emo leave.
Senioritis transferred over to Freshman year. Generally screws up your GPA for the rest of college.
I have froshitis, so I occasionally skip class, forget to do my homework, and fail my tests.