1.a word commonly used when there is nothing else to say in a conversation, or an awkward silence.

2.also can be shouted at a person who looks particularly unintelligent.

3.a rarely used term for "dunno"
person 1: yeah that was great
person 2: yeah haha
person 1:yeah?
person 3:fnuh!

ha! look at that guy, FNUH!

what time are we going to the cinema? fnuh!
by dizzee B May 10, 2007
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Fnuh is another word for fucked, as in being drunk/intoxicated
"Man i am so fucken fnuh'

"Look how fnuh mario is"

"We are going to get fnuh on the weekend"

"I have never been so fnuh before"
by FJC January 16, 2005
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