ass knife 

when your skateboard gets between you and the ground when you fall and catches you in the junk.

Argh! I missed the rail and got ass knifed!!

ass knife by Slyder February 17, 2005

big ass knife 

a big ass mutha fuckin knife, as in a big ass blady thingy! kill dem snakes on da plane

Dat be a big ass knife nigga!!!

big ass knife by bob the reindeer knife masacre September 30, 2013

knife ass 

The approximate 2 - 10 seconds of immense pain inside of a female's anus that comes and goes without warning. It feels like - more or less - a knife in one's ass.

Girl 1: *starts to wince in pain whilst squirming in chair*
Girl 2: Are you alright?!
Girl 1: *stops* Yeah, I just had a massive case of knife ass
Girl 2: Aw yeah I hate that

knife ass by deuxgatos January 21, 2011

Knife Yo Ass

A threat to cause pain using a knife or blade.

"you best step before I knife yo ass!"

Knife Yo Ass by DayDay January 4, 2004

Assknifed 

Where you wipeout and your board flies up vertically and hits you in the ball sack or up the crack of your ass.

Dude, I just got pwnt when I accidentally assknifed!

Assknifed by Psychopathic J January 5, 2008