A martini made with gin and dry vermouth garnished with a miniature, pickled onion. A spoonful or two of the brine/juice from the pickled onion jar is then added to make it dirty.
He went in for kiss and got his ass smacked thanks to his nasty onion breath from the dirty gibson he was drinking.

Mel Gibson prefers to drink several dirty gibsons before going on drunken, anti-Semitic rampages.
by drinkdrankstank August 3, 2009
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When one is on a drunken rampage, he has uninhibited drunk sex with jews while yelling racial slurs at them, then the next day claim that you are not racist. Now also known as the dirty Kramer.
Let's go find a few orthodox's im in the mood for a dirty gibson.
by Cobbs666 December 3, 2006
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Garnishing a martini with a pickle, then, upon finishing it, rolling the pickle in cocaine and sticking it up your butt.
Walter: The only thing better than a gibson is a dirty gibson.
by Everettville Dotorg May 9, 2009
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Having your best pal give you a reach around after you fucked him in the ass.
Tom gave Victor a dirty gibson last night.
by quentiano April 23, 2006
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