NAK

[from the ASCII mnemonic for 0010101]

1. On-line joke answer to {ACK}?: "I'm not here."
2. On-line answer to a request for chat: "I'm not available."
3. Used to politely interrupt someone to tell them you don't understand their point or that they have suddenly stopped making sense. See {ACK}, sense
4. "And then, after we recode the project in COBOL...." "Nak, Nak, Nak! I thought I heard you say COBOL!"
5. A negative answer. "OK if I boot the server?" "NAK!"

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