A person, usually part of a group, who kidnaps loved ones and friends unexpectedly and cuts off all communication to that person for extended periods of time, until its demands are met, usually involving pizza or other greasy foods.
The ninjas kidnapped her! We might never see her again, unless we give them each slices of pizza!
by Ninjafied August 27, 2009
Comes from the term Silent But Deadly (SBD): 'A fart that is not heard, but smells so horrid that it could kill.'
As ninjas too are silent... but deadly.
'Wind down the windows, I think there's a ninja in the car'
by I'mOldGregg April 21, 2009
Any badass lifeform that most often assassinates political figures, moguls, barons, lords, etc...
Damn did you see Turbine take down Steve Irwin...Sting rays my ass..it was all that ninja...spider.
by DJ Kag July 10, 2008
A silent-but-deadly fart normally released to assassinate unsuspecting bystanders in small cars, phone booths, and long elevator rides. These ninjas are known to have not only render average humans unconscious, but clear funeral homes, meeting space, classrooms, and other places where people would be caught with their guard down and nostrils open.
I almost died in at the office today when headed to the 47th floor in the elevator some jerk blew-ass released a ninja and everybody suffered from oxygen deprivation.
by Crunknyosystem October 01, 2007
Synonym for AIDS. Can't be seen and VERY deadly.
1. That girl has the ninja!
2. Keep fucking without a condom and the ninja will get you.
by Sandman409 July 01, 2006
Little stealthy dudes dressed in all black, carrying around swords and daggers, who jump out of trees and off of buildings to vanquish wrongdoers.
He snuck into the theater all ninja-like.
by Carrie =] June 23, 2006
The un-official term used to describe an internet forum member who possesses moderator powers, but no title. Ninjas are swift, silent and deadly. Ninjas edit and lock threads without warning often killing threads with a single blow and then quickly vanishing. Only the most trusted members become Ninjas. See Ninja Edit
Cleoent: *edited*
Cleoent: Damn, who edited my post? Where those ninjas at?:shifty
by oh_noes March 31, 2006
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