A verb most commonly heard in online FPS (First-Person Shooters.) It is the act of stabbing another player or person with a knife and thus killing them instantly.
A stabby thingy in your kitchen or in your purse NO BITCH IT IS A SHARP FUCKING BLADE THAT CAN HURST PEOPLE SO PUT THE GUNS AWAY AND MEET 2016 AND GET A KNIFE.thank you have a nice day
Dumbass: did u see that stabbythingy that she cut me with.
Me: a knife
Dumbass: yah that
Me: walks away comes back "POOF" no more dumbass RIP