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11.
Current/former Nine Inch Nails fans (hence, the "NIN" part of "ninnies") who originally met through the Net (old-school ninnies trace their roots to the alt.music.nin Usenet newsgroup, while more recent converts have been acquired through IRC, Live Journal and dating/marrying other ninnies), and who now get together periodically to consume prodigious amounts of meat, alcohol and curiously strong brownies, wear Reznor heater shirts and bondage gear, perform cutting-edge karaoke, and comandeer hotel lobbies 24/7 for shooting the bull, freaking out mundanes, making more bad in-jokes than was previously thought humanly possible, and impersonating N'Sync roadies.
Trent? We don't need no stinkin' Trent--we're ninnies for life, with or without him!
by Robin the mad photographer January 30, 2005
 
1.
Shortened version of nincompoop, a silly, idiotic person. can be used affectionately.
you went into the girls bathroom by mistake? you ninny!
by Shwaggy November 18, 2003
 
2.
Quite possibly the coolest insult ever. Short for nincompoop, it was used often in Victorian Europe and early North America. Insult of choice for monocole-wearing gentry, and anyone with a bit of class.
My, what a ninny! *monocle*

Ninnies + potatoes = sign of good will?
by Rivviko September 10, 2007
 
3.
1. An idiot
2. Short word for nincompoop
3. Someone who is afraid of everything and has no courage; see pansy
You are such a little Ninny!
by Turd Ferguson January 29, 2004
 
4.
short for nincompoop, a silly, stupid person. often used affectionately.
you went into the girls bathroom by mistake? you ninny!
by Shwaggy November 18, 2003
 
5.
nincompoop, idiot, moron, Piers Morgan
Piers is a big Ninny
by SusanHarHar October 02, 2010
 
6.
Small sized breasts
Most women are unhappy if they have ninnies
by Fisher March 23, 2004
 
7.
a Finnish term for breasts
My lady has nice ninnies.
by Wadeskie June 23, 2006