What is Apple Day?
1.
an annual celebration that takes place on October 21 celebrating orchards of blossoming apples every fall; celebrations include the making of apple cider and various 'apple based' games (usually takes place in United Kingdom)
Can't wait to eat loads of apples on Apple Day!
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2.
Apple day is code name for when you and your friends are going to pull a pretty awesome prank. Derived from pranks of throwing large amounts of apples at cars.
"Damn, man I cant believe its fucking apple day tomorrow"
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