The act of one person pooping into the ass of another individual, then, that individual poops the turd back into the 1st person's butt. This process is repeated back and forth until orgasm or election, whichever comes first.
That porno contained the dirtiest 'political exchange' I have ever witnessed.

or

The candidates sure had a heated 'political exchange' in last night's debate.
by Political Troll September 11, 2013
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A teenager who spends a few months up to a year in a different country experiencing a new culture, living with a new family, and going to a new school. Exchange students will make you question how and why you do things. If you are really lucky, they will bring you candy and other goodies from their home country.
Who is the new girl in chemistry who has an accent?

Oh, she is the new Italian exchange student.
by smartypants222 February 15, 2012
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Humankind cannot gain anything without first giving something in return. To obtain, something of equal value must be lost. That is Alchemy's First Law of Equivalent Exchange.
"Alchemy: the science of understanding the structure of matter, breaking it down, then reconstructing it as something else. It can even make gold from lead. But alchemy is a science so it must follow the natural laws: to create, something of equal value must be lost. This is the principal of equivalent exchange. But I learned that night that some things cannot be measured on a simple scale. My brother and I knew the laws of science, of equivalent exchange. The game required sacrifice, that something had to be taken from us, but we thought there was nothing more we could loose....We were wrong."

~Edward Elric (Fullmetal Alchemist)
by one/and/only/truth December 19, 2010
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People cannot gain anything without sacrificing something. You must present something of equal value in order to gain something. That is the principle of equivalent exchange in alchemy.
"In the early days, we believed that to be the one truth in the world." -Alphonse Elric
by The_Heartbreak_Kid June 6, 2005
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People generally have one experience or the other on Stack Exchange:

1. A great place to get answers to your burning questions. Whether it's about programming, computers, languages, drawing, writing, or much more, you're sure to get the answer you're looking for within hours.

2 An elitist network of forums where you're sure to get downvoted for asking a question deemed "too simple" by the o' so holy members. Spend hours writing out detailed responses to people's questions only to get trumped by a couple of sentences. A toxic community that should be kept away from.
Type 1: Just got my question about whether doughnut or donut is the more acceptable spelling. Stack Exchange is totally rad!
Type 2: Just spent 30 minutes correctly this guy's poorly written Rock, Paper, Scissors Javascript game. 0 upvotes and no thanks from the asker. Stack Exchange is the worst thing ever!
by DisgustingWeebs June 4, 2017
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An online dating service such as lavalife where you basically look through an online menu of girls and try to arrange a hookup. High volume traders on the seadonkey exchange frequently arrange to meet their prospective piece of ass in a public place so that if they end up being butt ugly they can easily bail on the chick. Other times, guys will have their friends go to the prospective girls place of employment to see if she is too nasty to hit up. It is a Generally Accepted Seadonkey Principle (GASP), that 95% of the girls on seadonkey exchange websites are repulsive. Yet, some men are attracted to the fuck and chuck aspect of the whorish online women. Seadonkey exchanges should be used sparingly and only in times of desparation as they will most certainly result in a large ashamed list.
Barry: Hey Levi, can you go to REI and see if this chick that works there is worth my time?
Levi: Did you meet her on the seadonkey exchange Barry?
Barry: Yeah, what's the big deal?
Levi: It's just that you already have the biggest ashamed list of anybody I know by far. You sure you want to do this?
Barry: Yeah man, I really need some head and my back massaging tool just doesn't get me off like it used to.
by Lazynutz July 4, 2005
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When you are eating a girls ass out and she farts in your mouth. You then hold the fart in your mouth and pass it from your mouth to hers.
"Man last night this chick and I were fucking, but she farted in my mouth when I ate her ass out"
"Did you swallow it?"
"Nah, man I just did a methane exchange and gave it back to her."
"Nice, dude"
by Casual Rapist May 24, 2013
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