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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anything you want it to mean fitting the situation.
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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The verb form of Ninja. To act like, have the characteristics of, or be a Ninja.
Stop ninjing, you keep sneaking up on me and scaring me.
by Rachel Applefield January 24, 2018
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To steal or take wrongly; to hijack; to snatch; most synonymous with "to jack"

One who ninjes is a ninjer, or in ghetto parlance a ninja.
that guy totally ninjed my pen
by usethisword September 15, 2007
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