Shaking the ketchup bottle is a euphemism for male masturbation. The metaphor comes from both the vigorous shaking motion applied to a ketchup bottle, and the "splooging" of ketchup when you've shaken it for long enough. Note: If what comes out is actually ketchup coloured, then you should very likely consult a doctor.
BRB - need to shake the ketchup bottle.

I was vigorously shaking the ketchup bottle last night.

I think I spent too long shaking the ketchup bottle - I'd ran out of ketchup by the time I was finished.

Shaking the ketchup bottle is a great way to pass the time.
by orangepony April 12, 2012
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