When you drink a milkshake that tastes heavenly enough to make you 'mmm' . Often accompanied by a smile, and some guy staring at you and thinking. 'What the f***.'
Some milkshakegasms aren't as drastic, whereas some can lead to jizzing your pants in satisfaction.
Fred: 'Look at that guy.'
Victor: 'Lol. That guy definitely just had a milkshakegasm.'
by i eat teddybears July 3, 2013
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