Poo knuckle

I’m not entirely sure , but she definitely has one.

No, no,no I mean she has a poo knuckle. For real for real.

Finger to the power of knuckle

When a finger is inserted up to the 3rd knuckle.

Dude, Gavin just told me Katie deceided to get a little freaky and go finger to the power of knuckle on him whilst providing oral pleasure.

five knuckle sandwich

hands used in barehanded boxing aka fisticuffs

So, the gloves went off and we engaged in fisticuffs feeding ourselves five knuckle sandwiches until one of us saw stars
After the argument I just fed him a five knuckle sandwich

Sixth knuckle deep

Puting you arm past the elbow inside somebody

Im gonna fist you so hard I'm going sixth knuckle deep!

Gimme knuckles

Another way to say fist bump

Imagine 2 people playing Darts for the same team of 4 players. One team mate scores 180 points with 3 Darts (taking the game, because their team needed to score 180 points to win the game)

Player 1: Holy Crap, 180!!
Teammate: Dude, gimme knuckles!!!
The winning team's 4 members all bump fists.

knuckle valley

The space on your hand between your knuckles. Ben White invented this term.

I have a wart in my knuckle valley.