Jacksis - Jacksis is what British people call the hole you poop out of

Jacksis is what British people call the hole you poop out of, or the part you stick your finger in when you're trying to clean it.

My friend got called jacksis after he tried to eat a whole bag of chips and then exploded.

I got called jacksis after I tried to clean my jacksis with a sock.

My dog got called jacksis after he tried to chew my homework.