5K1 

Also 5-K-1. Refers to someone who provides assistance in the investigation or prosecution of another, used in context to release them from otherrwise mandatory sentencing guidelines.

Related to the 2001 Federal Sentencing Guidelines Section 5.K.1.1

In the Geto Boys song G-Code: "Fuck a 5K1, check his P-S-I"

5K1 by LostGunMan December 26, 2006

5k1 letter 

a letter sent to the judge from the us attorney asking to depart from mandatory guidelines due to their cooperation with the government

Conspiracy to disturb meth is a mandatory 10 years but with proffering session a 5k1 letter
John helped create 2 fresh indictments so they agreed to put him on a 4 person indictment instead if he cooperated. He’s still in county while agents continuously pound him with “What do you have for me now?”

5k1 letter by connierobinsonkc December 31, 2022

5K1ll3d 

5K1ll3d is simply the 1337 sp33k version of skilled. It is an adjective used to describe a player's ability in that particular game. The player's knowlege of where their opponent is, where to place grenades, reaction time, ect, all attribute to 5k1llz.

"How did you know I was there? either you are hacking, or you are very 5k1ll3d."

"Tripping and falling off the side of that building was the most un5k1ll3d thing I have ever done."

5K1ll3d by Drüd October 19, 2008