1 definition by qwertyuiop3455mave

When wearing a shoulder-strap bookbag or laptop case, and you have slight to extreme man boobs, it accentuates these man-boobs causing a feeling that everyone is staring at your fatness.
Person 1: Dude, watch out on that strap.
Person 2: Why?
Person 1: You're developing bag-boob
Person 2: Damn. Everyone can see my man boobs?
Person 1: Yup.
by qwertyuiop3455mave November 16, 2009
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