to partake in the actions or activity of being a ninja. This includes sneaking, hiding in shadows, travelling on foot via rooftops, scaling buildings with a rope or grappling hook attacking/killing unsuspecting victims, using cheap tricks to evade and confuse.
1. "At night, I ninje."

2. "Where's Mike?"
"Oh, he's ninjing across town."
by Matt-a-tat-tat November 26, 2007
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a less offensive word for nigger
Don't be a nigger, you ninje.
by hardyyy September 23, 2008
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Displaying the abilities or likeness of the ninja.
Last night, no one knew we were present, which was in large part due to the fact that we were ninjing in the shadows.
by Nine Lives Co July 18, 2018
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To have sex, usually very quietly and in a fashion that will avoid detection. From the phrase "Ninja that bitch."
Most often heard in the gerund form "ninjing".
by Fern, Defender of Trees July 16, 2009
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ninj (v.): to act in such a manner that could be construed as causing trickery, disruption, and/or pain on those who instill one's wrath
Ninj (n.): any one of a number of people who enjoy, and in fact take delight in, causing mischief and trickery on those who deserve it; i.e., mauling someone
v. "I'm gonna ninj you, you bloody prick, if you ever say something like that again!"

n. "I am so a ninj!"
by ninjgirl April 13, 2011
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Damn you ninjed up that shot.
You look like a Ninj.
This Concert is hella Ninj.
by Trav is gay April 26, 2007
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