a state in which your brain is too lazy to do anything useful and make sense, so you just stay put on one place and do nothing. But not yet total-zombied for you can still blank stare at people and say "uh huh?"
Andy : "hey dude, what's up?"
Cez : ... (blank stare at the floor)
Andy : "dude?"
cez : (slowly look at Andy) "uh huh?"
(staring back to the floor)
Andy : "damn man, you're half-zombied today"