When you have sex in a public place with no one finding out, usually male on female or for a double cunt ninja female on female
by Jeremiah fink keister October 27, 2013

A Ninja is someone who leaves a party or pub/club without telling their friends, all stealth-like (usually because they're tired or drunk and don't want to cop flak for leaving early). This practice can become a common prank between friends, sometimes blowing up into an all-out "Ninja War".
Friend 1: Where'd Beamers go?
Friend 2: Umm, she told me she was going to the bar for another drink. Wait... That was half an hour ago...
Friend 1: Unbelievable, she's done a Ninja again.
Friend 2: That's it, Ninja War declared.
Friend 2: Umm, she told me she was going to the bar for another drink. Wait... That was half an hour ago...
Friend 1: Unbelievable, she's done a Ninja again.
Friend 2: That's it, Ninja War declared.
by Beamers202 July 23, 2013

The time when you look at a clock and realize that a large portion of time disappeared. It is NEVER 'ninja o'clock', because by the time you've realized the time, it's at least a half-hour after you expected.
Friend 1: "Dude, what the hell happened to the day? I had that interview for that job."
Friend 2: "Ninja-thirty happened, son... remember that 'I'm only going to play a couple games' Madden marathon we just had?"
Friend 2: "Ninja-thirty happened, son... remember that 'I'm only going to play a couple games' Madden marathon we just had?"
by Agent 14 December 16, 2009

A popular streamer that constantly wins games of fortnite. He gets paid to play video games for a living.
by OriginalName123789 August 20, 2018

to ninja: to chop a person in the back of the neck while open and there is no truce in affect. Or possible if you want to just be an ass whole or they are being a bitch you can breack truce. it is not a ninja if you hit there shoulder, head or face. there is a code for what u can do or how you can ninja someome. If u r truced w/someone u have to tell them when someone is gonna ninja them. if you have a truce with someone that is about to get ninja-ed and the person that is gonna ninja them you have to stay out of it and not say anything. you are basically nuetral.
-basic ninja:chop to back of neck
-sledge ninja: put both hands together as if you were praying then NINJA!
-Scissor Ninja: Ninja someone on the both sides of someones neck at the same time with both of your hands.
-basic ninja:chop to back of neck
-sledge ninja: put both hands together as if you were praying then NINJA!
-Scissor Ninja: Ninja someone on the both sides of someones neck at the same time with both of your hands.
jesse:Dude Carlos is fuckkin open, u should get him charles
charles:ok (ninja)
Hugo:damn carlos u got fuckkin ninjed ur lucky it wasn't a sledge or scissor
carlos:damn i must be a bitch and im irrational
charles:ok (ninja)
Hugo:damn carlos u got fuckkin ninjed ur lucky it wasn't a sledge or scissor
carlos:damn i must be a bitch and im irrational
by Milk-ninja May 28, 2009

A npc typically with blue hair who roams around colleges, perhaps most commonly a member of the LGBT community
by DickinsonsRealdeal January 2, 2023

A female with the characteristics of a mythical unicorn meaning very rare of a find. And that of a ninja in the fact that if your not careful she will sneak up on you and get you to fall in love with her
by Mtg187 July 9, 2022
