Knuckle reject 

When you attemp a fist bump, but the other person denies it.

"Hey bro, what's up?" (Attemp a fist bump) "No man, NO!" (Knuckle reject!)

Knuckle reject by JERALDtc May 21, 2013

Knuckle Theory 

A theory used by measuring the number of days in a month. If your index finger touches your knuckle of your hands, the month has 31 days, while if you touch the skin of your fist, it has 30 (with the exception of February).

Scott: Dude, how many days are there in August?

Dave: 31.

Scott: Isn't it 30?

Dave: Use the Knuckle Theory.

Knuckle Theory by OpeN333 October 22, 2013

knuckle banging 

to fuck the shit out of someones knuckles

i just finished knuckle banging cody and shaine so hard

knuckle banging by muncherofallass April 21, 2014

knuckle valley 

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

I have a wart in my knuckle valley.

knuckle valley by bcwhite96 May 4, 2014

knuckle flowers 

Fisting someone (usually a threat)

I'm gonna give you knuckle flowers if you don't tell me the truth!

knuckle flowers by Lerner May 17, 2014

Knuckle party 

A more low key/tame version of a fisting party.

The Mega Crew decided they didn't want too rough of a night, they settled for a knuckle party.

Knuckle party by JarJeff December 13, 2014

knuckle tat 

A trashy placed tattoo that could be a lot more original

Did you see his knuckle tats? How distasteful

knuckle tat by let's.be.honest December 28, 2014