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1.
GNI
girl's night in, a.k.a GNObut inside someone's house
me and my friends are having a GNI, we're gonna watch a cinderella story and freze-frame the make out scenes with chad michael murray
by 1123481321fs September 27, 2007
 
2.
GNI
Acronym for "Gays Night In."
Jen: "OH MY! I'm part of another GNI!"
Men: "Yes!! You are!!"
by DJ Andre October 28, 2009