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2.
Southern slang. None. A null set. Generally incorporated to complete a sentence defining being without.
You got rubbers?

No. Don't got ninnie.
by jiminton July 28, 2012
 
1.
Female version of a Nincumpoop. Someone who is being silly, stupid or without reasonable thoughts.
Sarah you big ninnie, you just put your car keys in the ice box

Or

If Beth is a class clown you might say
Beth is a ninnie
by ddlD2 March 17, 2014
 
3.
1.)A title reserved for people that have a defined humor style.

2.) A person that likes to use "that's what she said", and or, "Your mom jokes" frequently.

3.)Any female or feminine male.
Dang Katie, You are Such a ninnie
by ChrisPBaken November 02, 2010