noun - abbreviation for annual mancation during calendar year 2009 to attend MLB baseball games. Short for Baseball Trip 2009.
Boss - "Hey Bill, whats happening? So.. I'm gonna need you to go ahead and come in on Saturday, umm yeah"
Bill - "Sorry chief, this weekend is the start of BT2k9. I'm gonna have to ask you to leave my office."
Bill - "Sorry chief, this weekend is the start of BT2k9. I'm gonna have to ask you to leave my office."
by Bill Williamson March 07, 2009