A reference to a popular bar in Washington, DC that is conspicuously located next to the strip club Camelot. Claiming to visit this bar is a euphemism for having gone instead to Camelot.
Girlfriend waiting on the corner: "Wait, did you just come out of Camelot?"

Boyfriend having just come out of Camelot: "No way baby, I was in Sign of the Whale."
by DC hood rat October 13, 2011
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