At 

Symbol for the chemical Element astatine. Element no. 85, In between Polonium(Po) and Radon(Rn), The reason why chemistry teachers can't teach PoRn (porn)

Yeah there's nosy parents and age laws but Astatine is the only thing preventing us from seeing porn. Screw At.

At by pigeonVSstatue October 13, 2011

at 

A way to get someone's attention, verbally. Comes from Twitter's and Facebook's use of the @ symbol to identify a user or friend. Can be used instead of, or in conjunction with 'hey.'

In a group setting.
Joe: Hey, at Sheila, how was the exam today?
Sheila: Aced it!

at by pnwtease October 18, 2011

AT 

Acronym for Ass Talk. It happens when you ask someone as question and they have no idea what the answer is, so they start talking out of their ass. Usually it happens when someone is trying to sell you something in China. It can also come in the form of unwanted advice. Ass Talk is usually annoying, but once you recognize that you are hearing it, it is very funny.

me: "Mr. Chen, is this bag you are selling me real or fake?"

Mr. Chen: "Bag is reale, that is why you are buying it in my super lame store for a discounted price, and not in the real store. I know manufacturer. My quality is best."

Me: "well the price is kind of high, I bought it the same one in a shop next door."

Mr. Chen: "Not same quality. You buy no good, me sell you best product low price.

My wife: "this guy is full of AT. Lets get out of here!"

AT by Captain Niu B April 7, 2011

AT 

Acronym for the Appalachian Trail. Used mainly among hikers that have hiked and/or ran the trail, but by other people as well. The Appalachian Trail runs from Georgia to Maine.

"I'm hiking the AT this summer."
"Really? The whole thing???"

AT by Robert Watson July 23, 2005

AT 

An abbreviation of "awkward time." This is an extremely and overwhelmingly awkward occurrence that typically isn't easy to handle without making the person experiencing the AT feel terribly embarrassed or uncomfortable.

"Oh, I just walked by a tour group on campus as I was doing a walk of shame."
"ATs!"

AT by Last name means 5 in Italian November 20, 2011

AT 

Art Trade - used commonly on deviantArt

Wanna do an AT?
Sure man, but my art sucks.

AT by Lucky_Icecube March 17, 2017

AT 

Acronym for automatic transmission; an automobile featuring a gearbox that can automatically change gear ratios based on the car's velocity

My 2005 Nissan Altima 3.5 SE AT OWNS YOU!

AT by fleft January 26, 2005