1) The day of your birth.
2) The final step in procreation.
3) The day you were shat into existence.
1)It's Jim's birthday today! Let's celebrate the day he was a slimy ball of fleshy meat sliding out of his mother!
by SSBrando January 15, 2009
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The one day you want to put a gun in your mouth and everyone comes over to celebrate.
When you become old you're family will start talking about your funeral in front of you on this day. God Damnit! It's my birthday!
by someguy563 November 30, 2005
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They're great when you're young ("when I grow up, I'm gunna be...")
But then become a pain in the arse when you're like 48 ("you're nearly fifty! WAHAHAHA!").
Ooh yeah, ooh yeah, it's my birthday, it's my birthday!
by Merafel Estomar September 1, 2003
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The day 9 months after your "Uncle" Barney spent the night with your mom because her "plumbing" needed some work.
Older man: "Happy 10th birthday Timmy!"

Older man(to mom): "Reminds me of the last time I put icing on your buns."
by Menyae Shoemaker March 28, 2009
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"Dude, why are you so pissed?"
"Its my freakin birthday!"
by stephmey July 10, 2008
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A reason to drink. (see also: Halloween, New Years Eve, Independence Day, Easter, Mardi Gras, Cinco de Mayo, Friday)
On his birthday, Charlie consumed twice his weight in beer.
by asdfasdfasdfasdfg January 5, 2012
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