"Plonk" is also used in British English as slang for cheap, low-quality wine (from the French word "blanc" for white wine). This usage dates back to WWI and is originally Australian.
How fitting.
PS, don't even bother looking Urban Dictionary, you'll just be violated.....
I'm hoping this settles the matter.....
Later DUDE. SHIBBY!!!
Author's response
Whoa, you really looked it up. I wished I hadn´t looked at Urban Dictionary (but how can you NOT look somewhere when you´re told not to?!) because not it looks as if I had taken the idea for one of my upcoming chapters from there. Nevermind, I know I´ve had it before and so does Mr. Meatball. Thanks for being one awesome (female) dude! :)