American hockey player. Term is used when you are absolutely sure of something during an argument or dispute. It's a "Guerintee".
"Yeah Daryl, your a big lad now but when we were ten, I would have kicked the hell out of you."

"Shut up man, there is now goddamn way you would have kicked my ass, I was the toughest kid in my school."

"Yeah honestly I would, and you can put a Billy Guerin on that"

"Oh fuck really?...you know what, now that I think about it, I really was a bit of a soft lad when I was a kid"
by nothingbuttrouble May 22, 2005
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