knuckle bumper 

Another term for a lesbian. To get a visual example, bend both the index and middle finger of each hand and bump the mid knuckles together thus simulating two vaginas bumping each other as lesbians do to get sexual pleasure, such as the extremely hot act of tribbing.

Guy 1: "Hey dude, have you met the new girl? She's hot!"

Guy 2: "Yeah, but dude she's a knuckle bumper. There's rainbows and shit all over her social network profile."

knuckle bumper by MrFriendzone April 13, 2016

bumper knuckle 

slang word for fisting

i cant walk after being bumper knuckled.

bumper knuckle by daddy2272727 May 19, 2017

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