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characterized by someone who is bipolar. A Niveen can have episodes of pure genius, exuding natural talent and wisdom. However, these episodes are followed by incidents of reckless behavior indicative of someone who is mentally deranged. During these episodes a Niveen may shriek like a banshee while hurling objects at confused victims in close proximity. Therefore, it is recommended you steer clear of a Niveen when in public or when surrounded by shoes and/or kitchen utensils. Also, Niveens may eat their own babies.
"OMG she just put ketchup on her baby!! The Niveen is out of control!
by ubettareconize February 07, 2010