Under the stall

A manner in which mostly homosexuals masturbate or perform fellation by kneeling on the floor of a stall and facing the stall of their genetalia close to the person next to them.

Ugh this dorm hhas no glory holes, gonna have to do it under the stall

Under-roos

Underwear!!

*Note* (Usually used when refering to briefs)

Greg's under-roos are to skidmarks as canvas is to paint.

under-duck

running under someone as you push them on the swing

I kicked Kerry in the head as he under-ducked me hard.

under beard

When a teenage boy is not yet man enough to grow a full beard, but instead grows ugly/nasty stubble under the chin and above the throat.

Tyler rubbed his under beard making a loud scratching sound.

under the pen

A writing term inspired by the phrase "under the knife". 'Under the pen' is a phrase in writing (particularly in Hollywood screenwriting) to mean that an already completed work is currently undergoing revisions by the writer.

JUSTIN: "Hey, Alex, how's that screenplay of yours you sold last year to that big studio?"

ALEX: "Well, that big studio wants some revisions made, so it's under the pen right now."

Under-rise

The feeling of your undergarments riding up into uncomfortable positions.

I just picked this wedgie, but I can feel my undies starting to under-rise again!

Under the Bottle

Synonym for Under the Influence but strictly when speaking about drinking alcohol, usually beer because it is in a bottle.

Guy 1: Man, I was so under the bottle last night after I came home from the bar that I could barely walk.
Guy 2: Yea that was funny, lets get under the bottle again tomorrow.