When I come across a word that I am unfamiliar with I go to merriam-webster.com and look it up...you know building my word power (ha). I noticed a Top 10 list of British words and decided to take a look.
I LOVE number 5...(I really need to get out more)
cheap or inferior wine
"Fine diners are drinking premier cru wines at plonk prices as a bring-your-own booze revolution gathers pace in Britain's best restaurants." – Robert Booth, The Guardian, June 20, 2010
About the word:
Plonk is a shortening of the earlier plink-plonk, and it may be a modification of vin blanc, which means "white wine" in French.