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1.
To "do a Colin" is a synonym for any broken promise/lie.

Spawned from the twitter trend #IamColin. In reference to twitter user @cwarr07 who promised to donate 100 pounds to a cancer charity if he lost a bet. He lost and refused to pay. This started a twitter trend where people have been donating on his behalf to the Sir Bobby Robson Foundation raising almost 1000 pounds.
John: "Fred promised to help me with moving house last week. On the day he never showed up or answered his phone."

Terry: "Fuck him, he's always Doing a Colin"
by toonarmymia July 29, 2011