1. To injure or kill someone with bruce lee style martial arts skills.
2. To unleash your ninja rage on someone to has pissed you off or has inferior ninja skills
"my boss fired me today, im gonna ninjafy is ass"
to make something into a ninja!
Bob: that kid's a loser and he can't defend himself
Rob: yeah let's go mug him
Bob: no i got a better idea, i just saw the karate kid..let's ninjafy his ass.
Rob: dude, you're amazing. lets have gay sex later
1.when you do something ninja-like (most likely attacking in a ninja fashion) to someone completely unexpectedly.
2. also can be used as a threat. usually not very scary.
3. generally leads to the injury of the person doing the ninja-fying.
sophie : dont make me NINJAFY you!
kat : you are insane.
sophie : i tried to ninjafy him but it resulted in the breakage of my arms.