The use of the 'not' joke. Primarily an American idea, the 'not' joke is American sarcasm at its finest.

The lack of sincerity in sarcasm is usually conveyed through tone of voice, but with Americans and their famed linearity of thought, sarcasm often escapes them. Therefore, to make their statement seem sarcastic, they overtly announce it so, by sharply adding 'not' on the end.

Painfully guilty of 'Don't Explain the Joke.'
Group of people eating a meal:
"Wow, this food tastes great...not!"
"Why did you say 'not'?"
"Kelly over there's a yank. Had to slip in some American Sarcasm so she'd get it."
by kremlinjoe June 16, 2009
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