When one twin is clearly more attractive, cool, or likable than the other twin. After suffering through a lifetime of people asking where the "hotter" or "funnier" twin is, the less desirable twin inevitably forms a "chip" on his or her shoulder, thus making the chip twin even less enjoyable to be around.
1.

Party host: "Where is Andy? I love that guy. He's hilarious."

Chip twin: "Why is everyone always asking me where Andy is? How should I know? I don't know where he is all the time! I'm just as funny as he is!"

Party host: "Listen chip twin, you're not invited unless you are with Andy. Robin didn't go around trying to fight crime on his own."

2.

Guy at bar: "So how do you two know each other?"

Chip twin: "We're twins."

Guy: "No, seriously. How do you know each other?"

Chip twin: "We are twins."

Guy: "Come on. Seriously, how do you know each other?"

Chip twin: "You're an asshole."

*Twins walk away*

Guy: "What did I say?"

*Guy 2 walks up*

Guy 2: "Fucking chip twins, man."
by ChetWhitlock September 25, 2014
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