Pre Ketchup

The watery bit of ketchup that comes out when you go to use the ketchup but the bottle hasn't been shaken up or it has been left a while without being used. This leads to a puddle of watery ketchup being left seeping onto your plate and probably on your hands.

"Ew, I forgot to shake the bottle, now there's Pre Ketchup on my chips."

"Don't forget to shake the bottle or you'll get Pre Ketchup."