A fork of Rural Dictionary
Shortened to the Robin Ruth Amsterdam cap.
Dam caps are notoriously worn by Chavs for their low cost and similarity to the DSQUARED cap.
Person 1: Hi guys
Person 2: Aye
Person 1: Is no one going to mention my cap?
Person 3: Why what?
Person 1: It's my Dam cap!
Person 4: What the fuck's that?
Person 1: I don't know but everyone in Blacon's wearing it!