(adj.) Sarcastic term used to describe the state of feigning a full schedule of events when one, in fact, has no obligations whatsoever for the period of time in question.
Friend 1: I can't hang out tonight, I have a million things to do because I am super-busy.
Friend 2: Wow, I did not realize you had so much going on right now.
Friend 1 then goes home and sits in front of the tv or reads a book for the rest of the night.
The "busy" that excludes the important people in ones life.
Implies "I've got better things to do than spend time with you. Can't you see how busy I am?"
"I can't see you tonight; I'm super-busy at the moment"