In reference to someone who is ridiculously and outwardly stupid, as in jumping off a plane with a backpack instead of a parachute; absurd unintelligence.
I talked to that tool for more than an hour, and he DEFINITELY has the backpack.
Verb: to put a backpack on a very drunk person before they go to bed, so as to keep them on their side in the recovery position and stop them from rolling onto their back so they don't choke on their vomit in their sleep
We're going to have to backpack Ally tonight and make sure to put somethingheavy in it because she just finished a fifth of vodka