Top Definition
I gathered some facts about them:

Ninja don't sweat.

Bullets can't kill a ninja.

Ninja invented skateboarding

Only a ninja can kill a ninja. Regular humans are useless.

Ninja never wear headbands with the word "ninja" printed on them.

Ninja can breath underwater anytime they want.

Ninja can change clothes in less than 1 second.

Ninja don't smoke, but they do use smoke bombs.

Ninja always land on their feet. If they don't have feet they will land on their nubs.

Ninja invented the internet.

Ninja don't eat or drink very much, and they never have to go to the bathroom.

Ninja always move to America when making a new start as a non-assassin.

Ninja don't play sports. Unless killing is a sport.

Ninja can crush golfballs with 2 fingers, any two fingers.

Ninja have a bad temper when they lose at anything. They will usually cut off the winners head before they have time to gloat.

Ninja lie all the time. Even when the truth serves better, ninja will lie anyway.

Ninja swords are always straight with a square handle guard. Always. Curves are for girls.

Lack any personality

Wear headbands

Fight skillfully with any object

Can remove a spleen in one swift motion

Live in your house secretly for days

Can remove their shadow if needed

Hurl shurikens

Go anywhere they want instantly

Catch bullets in their teeth

Kill themselves if they make a noise

Can run 100 miles on their hands

Train 20 hours/day starting from age 2

Have cool words like Seppuku

Are masters of disguise

Can hover for hours

Flip out and kill everything

Are completely self-sufficient.

Split planks vertically with their nose

Can hide in incense smoke

Kill people.

Ninjas are the best guitar players. Ever.

Ninjas do NOT wear spandex.

A Samurai is NOT a ninja.

Dragon Ball Z characters are NOT ninjas.

If you see a ninja, he is NOT a ninja.
Some guy: "Ninjas are totally sweet"
Some other guy: "True true"
by sam paulin August 12, 2005

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An unending game involving more than one participant. The objective of ninja is simple. Fart in your hand, sneak up behind the unsuspecting victim, then cover both their nose and mouth in attempt to "assassinate" them. Ninja can start at any time. There are no rules or restrictions to your assassination attempts, but they must be carried out in the fashion mentioned above. The game will end when the other party specifically expresses they want to quit the game. (If they know what the game is.) Or if they gag or excrete any type of bile. If none of these are met, then the came will continue until then.
Me and bob were hanging out in the kitchen one night, until I farted in my hand while he was busy and cuffed his mouth and nose in attempt to assassinate him like a Ninja.
by Jack wangerdoodle. February 21, 2014

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Someone who has the ability to mindfuck others. Someone who is stealth enough to complete missions with other ninjas that involve high risk situations. A ninja can usually "ninja" information out of other individuals who are clear 'un-ninjas'.

Ninjas are usually dressed casually, and people don't usually peg these people as actual ninjas, but rather, ordinary and normal girls. Watch out though, there couldbe a ninja at your workplace.

And she could ninja the shit out of you.
co-worker: blah blah blah blah blah

ninja: (in her mind) - good to know I just ninja'd the shit outta you bud. I'm going to go tell my other ninja this classified information.
by ninjatwoxo July 21, 2011

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A word used to describe something that is friggin' awesome.
Person 1: Did you watch that basketball game last night?

Person 2: Ya, omg, that move that that guy did was like, so ninja!!!

Persoon 1: IKR!!!!
by Mr. Hedgehog December 21, 2010

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A racial slur directed towards a person of African-American decent. Used in place of nigger.
That ninja is being loud.
by ninjabirds September 21, 2010

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someone who is using the perk "ninja", or "ninja pro" in "Call of Duty: Modern Warfare II".
In a free for all

Ninja:

"Ooh I'm gonna sneak up on Erik B Red, and kill his ass...Bam!!!! How you like them apples?!?!?!"

Me(with a heartbeat sensor):

"Damn ninjas!!!!! I'm gonna kill you ninja!!!!"
by Erik-B March 12, 2010

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An assassin that according to the show 'deadliest warrior' can get totally owned by a Spartan.
Hey did you see that spartan kill that ninja?
by Dudewhereismycar? April 30, 2009

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A phrase used in place of the word "nigga" It's a more fun way to talk to your bros without a white guy getting funny looks from black guys for saying nigga!
CJ: Wassup my ninja!
Darren: Wassuuuuup!!
by NastyDelicious May 27, 2014

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