nun4u means "None for you".

It's a 'no' response/phrase to ridiculous suggestions, questions and or requests.

Originally used by Web developers and designers for a small Webs community and has grown in popularity sense then. It is now even used as an anit-theft marketing strategy.
CLIENT: Hey, love your work! Can I have a free design?
YOU: NUN4U

FRIEND: I don't understand why you can't just agree with me?
YOU: nun4u

RANDOM PERSON: Hey!!!
YOU: nun4u
by AlterPoser November 3, 2012
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