Undersack

The underside of a man's ball sack.

Her tongue gently caressed his undersack as it moved back towards his taint.

by JizzlePizzizle August 30, 2010

undertickle

The act of smacking a bitch between the ass cheeks and tickling her clit...all in one motion.

Undertickle that ho.

by BIG OLE BLACK GUY November 9, 2013

Underbutt

When girls wear short shorts and you can see the bottom part of their butts.

Damn did you Ashley's shorts? Her underbutt is completely exposed, and it caused me to bust an instant nut.

by Tinnysman July 11, 2018

undebunkable

Unable to be debunked.

Cheese: "It sounds like he plays a similar role to Toby, which is undebunkable."

by Bones_Malone July 2, 2019

undertuck n' suck

when a man tucks his erect penis between his legs and presents it to another person to suck from behind.

i was feeling frisky so i gave the woman the old undertuck n' suck

by blumpkinboychaps April 3, 2009

Underbum

When a female has a second bum

almost like a double chin

"does my underbum look big in this?"

"does this skirt emphasize my underbum?

"underbum is way rank"

by Chickenpastababy October 13, 2011

underbutt

The second butt created below the original butt by tight underpants, where the elastic is doing all the work, under tight pants.

in my jogging tights i have an underbutt and a muffintop and in between is my ba-donka-donk

by tiffawiffa April 21, 2009