Something you yell when things aren't going well.
Or
A name you call someone who just really fucked up.
Or
Wool or cotton garment for the penis.

Also a character in a graphic novel of the same title by Brett Mckinney.
Ron:Oh my god, is that your sister with salami in her bum?
Roger:AH Cock Pyjamas!!
by Brettemo April 23, 2007
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