The act of not properly defining a word or action. The Actions or Words that cause a muff can have consequences. More of a Cincinatti term but has the same definition as "screwed up or messed up."
Usually when somebody says someone has a boyfriend or girlfriend and then does not to a friend. Causing the person who is looking for someone to be lonely for a night.

I muffed up last night
by muffer69 January 2, 2011
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An ungodly hairy cooch. A word to use instead of "douche bag" or "pussy" when insultind another individual.
STFU you muff! Fuck yourself in hell, you muff!
by G-Shizzle November 16, 2005
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Back in the 90's this word meant being smacked upside the forehead when you least expect it.
Boy 1: Hey, want to see something cool?
Boy 2: Yeah.
Boy 1: Muff.
Boy 2: Ah! What you do that for?
Boy 1: HA HA HA! You walked right into that one.
by Falap January 28, 2010
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Mandatory ugly fat friend. Every hot girl you know in your life has one of these. They are often known has enforcers, body guards, and offensive linemen. Not sure the reasoning behind it, maybe the hot girls want to make themselves look better, but just always make sure you beware of the MUFF...
There goes another MUFF
by J ROG809 October 4, 2010
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This word is widely known as another word for a vagina. ALTHOUGH this definition states that the word muff is a shortened form of saying "motherfucker."
I'm fresher than a muff.

You're such a muff.

I'm tired of these muffing snakes on this muffing plane.
by SlamminMuff69 April 27, 2011
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A)A Sexy Royal Scene Kid
B)Delicious Pussy
A)Queen Muff says, "Die!"

B) I beat that Muff up!
by HappyTimePrincess February 16, 2007
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It is a surname. I think the name comes from Yorkshire and quite a few people from America have it as their last name!
Joanna Muff or Jonathan Muff.
by Anonymous Name April 1, 2007
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