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The phenomenum of the pleasure that is McDonalds transfered into to sheer euphoria as you consume the large variety of artery clogging cuisines, instantly spreading happiness across your face in the form off a smile.

Also known as the McGrin
Slim Jim: Dude look at that guy at McDonalds, he's Gianormus! I give him 2 months left to live tops!

Small Paul: Man, don't worry bout it! Look how happy that dude is eating his Big Mac, he'll die with a McSmile on his face for sure!

Slim Jim: Ah yes, the good ol' McGrin...lets go get a burger!
by Wollf April 07, 2010
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