Knucklebob 

Fingering your bootyhole or the bootyhole of another with your middle finger up to the third knuckle.

Beth was squirming last night when I did a little knucklebob.

I can’t shit today. I knucklebobbed myself last night.

Knucklebob by Eaton Holgoode October 6, 2017

Philadelphia knuckleball 

getting jacked off using a Philly cheesesteak. cheese sauce only. then rubbing the sandwich in your partners face while they eat it afterwards.

Are you hungry? I want a Philadelphia knuckleball

Philadelphia knuckleball by chapsfranklin September 3, 2016

Arkansas Knuckleball 

When engaging in intercourse with a woman from behind in the vagina, a quick, sudden and forceful penetration of the anus. Often occuring as an accident, it may also occur as a "How do you do!" to simply ring her bell.

Last time I was bangin'-it-in with that bitch, I gave her a donkey punch, so to spice things up, I gave her the ole' Arkansas knuckleball!

Arkansas Knuckleball by AssInClass December 21, 2008

Knucklebuster

A car, usually an old American car (1930's-1970's) who seems determined to skin, slice, and slash the hands of every mechanic who touches it, regardless of their skill-level. Resistant to tools, penetrating oils, vice grips, and laws of physics. Any bolt that is in this car will STAY in this car, whether you want it there or not, and if you try to remove it, it WILL break off, and leave you requiring 15 stitches in the process.

Holy Hell.........that '49 Mercury just tore my whole hand open, and all I was trying to do was change her damn oil!! What a knucklebuster!!

Knucklebuster by crackedheads666 August 2, 2010

knucklebumped a floater 

when one's aggressive ass-wiping causes him or her to forcefully strike the chocolaty log within the toilet bowl.

i was taking a behemoth dump on my break before i looked at my phone and saw that i had only one minute 'til punch in time. i was wiping so aggressively/quickly that i, accidentally, knucklebumped a floater.

knucklebumped a floater by todd beanfeather February 24, 2009

Knuckleball 

A crazy shot in soccer where the ball moves side to side up and down and has and an unpredictable movement and is the Goalkeepers worst nightmare! Most knuckleballs only Alem Torlakovic ( Soccer Skillz82) can do!!

Alem has an unreal knuckleball !

Knuckleball by TorrujGoat November 11, 2019

Knuckleball 

A baseball pitch which follows an unpredictable path. Very difficult for batters to hit and pitchers to throw. Only a handful of pitchers in the major league actually utilize it.

Tim Wakefield Throws the knuckleball so good, it literally corkscrews.

Knuckleball by Lutzie October 7, 2009