Ninjask 

When someone steals loot (ninja looting) when they could have just asked. Found commonly in MMORPGs such a WoW.

Dude, that guy totally took that without asking. What a Ninjask!

Ninjask by Meripz September 12, 2014

ninjas cutting onions 

A slang term for crying while observing something tearjerking, such as a sad film scene. This refers to both a ninja's alleged stealth abilities, and the irritation of the eyes by the fluids in an onion.

I was watching The Notebook yesterday. Damn ninjas cutting onions the whole time..

ninjas cutting onions by Intelligence001 December 17, 2016

ninjasaurus

Something that is super awesome; greater even than dragons.

Guy 1: Did you see that arnie film last night? He was fighting 10,000 ninja midgets riding velociraptors that have tommy guns for arms... on a space volcano that's about to erupt... using only a SHARK CANNON.

Guy 2: Dude, that's ninjasaurus.

ninjasaurus by Squeeeak January 8, 2008

pirates vs ninjas 

A popular fight between two entirely different groups. Based on two different internet subcultures, Pirates and Ninjas, as two very different stereotypes battling out to death. May sometimes have robots, cowbows, or ghosts added to it. The phrase is also used as Ninjas vs Pirates.

One Piece Nerd: Pirates would totally win in a battle between Pirates vs Ninjas!

Naruto Nerd: No! Ninjas always win!

pirates vs ninjas by SuperCowManTypePerson October 2, 2006

Nintendo Ninjas 

Nintendo Ninjas are people who drove around suburban area looking for people using illegal ROMs of their games.

The Nintendo Ninjas took down Plainrock124!
I'll be next I used a ROM.

Nintendo Ninjas by PhotonNitron August 8, 2020

Ninjas 

True ninjas cannot be found. Not even on urbandictionary.

Bob: "Hey have you seen any ninjas lately?"
Ray: "No, I don't believe in ninjas"

-Bob is secretly a ninja

Ninjas by wayfinderisaac October 4, 2012

onion ninjas 

They sneak up you when you're watching a movie and a real touching scene comes along and all of a sudden tears are streaming down your cheeks. Hallmark movies are infested with onion ninjas.

We were watching the movie Crash when that little girl ran outside to give her daddy the "invisible cloak" just as the angry Persian guy shot at him, and we all thought he had shot Michael Pena's daughter--only to discover the Persian guy's daughter had earlier put blanks in his gun...oh boy, did the onion ninjas sneak up on everyone when we learned the little girl was OK.

onion ninjas by Indybreadman January 9, 2019