Cotton Headed Ninny Muggins 

1) A moron, idiot, dumbass, and overall stupid.

2) A human who accidentally got into santa's bag, and was raised by elves, who because of his human form, cannot make toys as fast as the elves and is inferior.

3) An inferior toy-maker.

Buddy: "Why don't you just say it? I'm the worst toy-maker in the world. I'm a Cotton Headed Ninny Muggins."
Elf: "No Buddy, you're not a Cotton Headed Ninny Muggins. We all just have different talents, that's all."

Cotton Headed Ninny Muggins by AnAsian2010 December 19, 2009

cotton headed ninny muggins 

One who thinks he is humorous and/or lacks brain capacity; a doofus

Notice how the two previous posters before me are, themselves, cotton headed ninny muggins's?

cotton headed ninny muggins by Ctrl April 22, 2006

cotton headed ninny muggins 

An insult used by elves

Buddy the Elf: "I'm just a cotton headed ninny muggins!!"

cotton headed ninny muggins by Papa Elf13 January 1, 2012

Clan Ninny Muggins 

Clan Ninny Muggins is a clan in the popular app clash of clans. It is led by the fearless leader, Geoffpac and is a very active clan. Being in clan Ninny Muggins is not only rewarding in it of itself it's fun. The clan is an up and coming clan with a range of levels for players starting in silver rank all the way up to master. Ninny Muggins is a diamond in the rough for a clasher.

To be a member of Clan Ninny Muggins is to be part of the Ninny Muggins family.

Clan Ninny Muggins by Riptide Tiger July 28, 2014

cotton-headed-ninny-muggins 

a diss/insult in a funny, babyish way. It adds humer to any harsh fight and you may hear it coming from a whole range of different ages.

your such a cotton-headed-ninny-muggins! what is your problem

cotton-headed-ninny-muggins by stick it January 1, 2006

cotton headed ninny muggins 

Somebody who feels like they can't do something right.

Buddy the elf thinks he is a cotton headed ninny muggins because he can only make 85 etcha sketcha's instead of 1000 like the other elves. He is NOT a cotton headed ninny muggins because he is a human as pappa elf tells him. A good example of a cotton headed ninny muggins is somebody that blows a country to pieces because they THOUGHT they had weapons of mass destruction. What you know somebody that did that? Wow then we all know a cotton headed ninny muggins!

cotton headed ninny muggins by Cheeky Elf September 25, 2006

Cotton Headed Ninny Muggins 

An Emily

Emily Gagnon is such a "Cotton Headed Ninny Muggins"

Cotton Headed Ninny Muggins by Jimbo Anvil March 3, 2011