Top Definition
The true usage of the phrase is to claim that you simply 'do not know', however, the phrase is often interpreted as 'Fuck Nose' which may cause offence to the listner. This mis-interpretation is often replied to using 'Cunt Face' which is regarded as the appropriate answer.
"What time is Adam supposed be be here?
"Fuck Knows"
"Only asking...Cunt Face"
by Mystick Havok January 21, 2008

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An abbreviation or slang used to by many for a way to say "I don't know"
Boy1: Dude, what's the time?
Boy2: Fuck knows
by Dalmas January 02, 2014

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One side has the word, one side has the definition. Microwave and dishwasher safe. Lotsa space for your liquids.

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The Urban Dictionary T-Shirt

Soft and offensive. Just like you.

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The Urban Dictionary T-Shirt

Smooth, soft, slim fit American Apparel shirt. Custom printed. 100% fine jersey cotton, except for heather grey (90% cotton).

Buy the t-shirt