In its simplest sense, the tendency for all things to go from order towards disorder. It is like the one way sign for energy flows in this Universe.
The best example is a hot cup of coffee. You walk into a coffee shop and check your pockets that yes, you do indeed have some coin of the realm that you spent time and energy to acquire somewhere else. This coin is therefore concentrated time and energy or effort. You then walk up to the counter and order (key word here) a hot cup of coffee. The Barrista, who has an understanding of what you want, then reaches for a cup that someone spent time and effort making, and someone made an effort to clean. He then pours in this fluid that contains pure (hopefully) water that has been heated (we pay the power company for the heat) and poured over these magic beans that came from far away, with many people involved with ships and trucks burning fuel so that these beans could arrive here. This cup of coffee is indeed a highly ordered structure in the Universe. But today, instead of drinking it, we are going to perform an experiment. If we let the cup of coffee sit on the table long enough, say 30 minutes, what happens? It gets cold. The heat energy that we paid for is no longer concentrated in the cup. It still exists, but in the room not in the cup. This is a gain in entropy. If we let the cup of coffee sit there long enough, say 4 days, we notice that some of the water that we paid for has evaporated. It still exists as water vapor in the room (probably attacking the wallpaper) but not in the cup. This too, is a gain in entropy. By this time the Barrista will probably come along to kick us out, after all we've been here 4 days and haven't actually drank any coffee. If he does kick us out then he will have to clean the cup, spending time and energy and hot water, to bring the cup back up to a useful higher energy state, ready for the next customer. This would be an example of negative entropy. But he had to spend more energy elsewhere to accomplish this.
But let's say he doesn't kick us out. If we are still sitting here watching the cup in about 30 years when the building falls over, breaking the cup, then this too is a gain in entropy.
I am one of the few people on the planet to tell you that negative entropy = life (localized), in thermodynamics this would appear in an equation as -Δs (pronounced minus delta s).
by September 14, 2008

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Top Definition
Physics aside, the inevitable and steady deterioration of any system or society.
The world's entropy will be certain if global health care, poverty and crime are not dealt with.
by June 08, 2004

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The degradation of the matter and energy in the universe to an ultimate state of inert uniformity
by July 21, 2003

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1.)all organic matter breaking down, even as you read this; and, yes, you're breaking down too, doesn't it feel great? :)

2.) a rocking motherfucking song off of Bad Religion's Against The Grain album
1.)i was sad when my canary died, but then i realized it was just entropy in progress. then i got a twelve piece from KFC.

2.)Random blobs of power, expressed as that which we all disregard. Ordered states of nature, on a scale that no one thinks about...

Hey, Entropy! Turn it up louder, educate the masses...
by January 05, 2004

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Josiah Willard Gibbs (1839-1903), US physicist and absolute genius, described entropy as mixed-up-ness. The more mixed-up something is, the more entropy it has.
Washing machines are good at making entropy with your clothes.
by March 08, 2013

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hidden somewhere in the Chemistry Goddess' classroom.
May luck be with you that you find it.
Life without entropy is like life all Tuesdays.
useless and horrible.
ex. entropy has been found on fume hood, television set, smart board, under cabinets, etc.
by January 05, 2010

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chaos misunderstood.

People just don't know any better
Entropy is chaos misunderstood.
by October 03, 2004

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