Basically another word for cool. Except cooler, as its the word Ninja. Similar to badass in defintion yet far more badass, i think the best explanation of this word is infact 'Ninja'.
This is going to happen. It's Inevitable. It's going to happen big.
It will grow and spread across the Internet like wild fire with a shuriken.
*Roundhouse Kicks someone through a wall*
"Woah that's so frickin' Ninja!"
*A very nice hat*
"That hat is so Ninja!"
*Walks on the grass when there is blatantly a sign with clear instructions not to*
"Shit, that dude is ninja."
"What a queer"