swaffling
The act of slapping something with a semi-erect penis. It's derived from the Dutch verb "swaffelen".

In 2008 it won the title "Dutch word of the year" in a yearly held competion where the Dutch speaking public can vote online which new word, that originated in that year, they liked the most.
It had gotten a lot of media attention because a Dutch student "swaffled" the Taj Mahal on a school trip; and got expelled from his school for that action.

Recently Brittish carshow host Jeremy Clarkson mentioned it in a talkshow (BBC Qi), where he gave the definition: "To bang your penis against the Taj Mahal".

He also mentioned the word on the fifth episode of the new carshow "The Grand Tour" which was hosted from a tent in Rotterdam (the Netherlands).
The Dutch boy that boasted about swaffling the Taj Mahal on his school trip got expelled from his school.