A metaphorical shindig in one's pie hole to which a large amount of people are invited. Often, but not always, connotates good taste, depending on the clause that comes after this phrase.
Positive: "It's like there's a party in my mouth, and everyone's invited!"

Negative: "It's like there's a party in my mouth, and everyone's throwing up."
by Zeke April 9, 2005
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1)a good feeling in your mouth
(a reference to a Simpson's episode when Ken Griffey Jr. tries Mr. Burns nerve tonic)
1)It's like theres a party in my mouth and everyone's invited!
by jonnnnnnnnnny July 21, 2006
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wen sum1 ejected der cum into ur mouth
rosney ws givin charlie head n he put his parti in her mouth n tld her 2 swallow it wen chante his grl came in now rosneys in hospital
by st. mick July 12, 2004
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