from: the on-line hacker Jargon File, version 4.2.3:

plonk excl.,vt. Usenet: possibly influenced by British slang
`plonk' for cheap booze, or `plonker' for someone behaving stupidly
(latter is lit. equivalent to Yiddish `schmuck') The sound a {newbie}
makes as he falls to the bottom of a {kill file}. While it originated
in the {newsgroup} talk.bizarre, this term (usually written "*plonk*")
is now (1994) widespread on Usenet as a form of public ridicule.
St00oid is as st00pid oes. *PLONK*
by HTH January 26, 2003
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The sound a user makes as it hits the bottom of another user's killfile bin
Some AOL user wrote:
> <snipped pointless drivel>

by the_nerd December 02, 2003
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in Australian slang -

1: wine. usually referring to cheap wine but not neccessarily.

2: to place something down on a surface (even one's bum).
1: do you reckon a couple of bottles of plonk will be enough for dinner?

2: hey, come'n plonk your bum down and watch the movie, darl.
by periwinkle January 13, 2005
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A word used on message boards as a response to some turd, to let them know you've just put them on ignore.
Tom: I hope everyone had a good day today.

Turd: Duh, it's night here.

Tom: *plonk*
by Tom Joe December 22, 2006
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rhyming slang for cheap white wine.

bottle of blanc (white) = plonk
bring some plonk.
bring a bottle of plonk.
by cat rose of October 03, 2007
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A shorted version of plonker meaning a idiotic, moronic, stupid person.
You're such a plonk, spilling all the milk.
by CheekyCharcoal July 24, 2010
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