The day you successfully fill your girlfriend with a total of one gallon of cum (1,000 deposits) during your relationship
“Hey man have you done the homework?”

“Nah. I’ve been trying really hard to reach gallontines day
by Giggles&Pooh October 16, 2020
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A holiday celebrated on February 14th by eating an entire gallon of ice cream.
Allison: "Happy Gallontine's Day Nicole! Would you like to come over and celebrate by eating an entire gallon of ice cream?"
Nicole: "Do we have to share a gallon of ice cream between us?"
Allison: "Don't be silly! We EACH get to eat a gallon of ice cream, as the tradition goes of course."
Nicole: "Sounds great! I'll be sure to wear sweat pants!"
by dallisor February 5, 2014
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A holiday celebrated on February 13th by drinking a gallon of beer.
Chad: Bro, are you celebrating Gallontine's Day this year?
Jason: Yeah brah, got my PBR.
by ChickenFlucker February 14, 2017
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