A slang term used to describe a women's vagina. It originate's from the hit UK TV comedy 'Bo' Selecta!' and is suited to a generic European accent.
Also, if asked to show your 'potakian', a gesture is made with the mouth to show an inside view of a vagina being tongued ('licked out' etc). This is done by pinching the the top lip with one hand, and the bottom lip with the other. The top lip is then pulled up, the bottom down, and the tongue is then wiggled within the hole.
'Let me see your potakian!' (then followed by the mouth gesture)