When a friend, due to circumstances, leaves a bong of theirs at your place for safekeeping.
Dude, I'm going on vacation for a few weeks, can you bongsit for me? My roommate broke my last one and I don't trust him...

Person 1: Dude, I love your bong!
Person 2: Oh, it's not mine, I'm just bongsitting it for the summer.
by frostycakes July 23, 2010
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