What's up with these weird sounding words?

I was thinking about a way to improve the performance of economics students and decided that definitions might be a good way to help them. So if your a student wondering what the heck your professor is talking about in class. This post may help you.
First one is "utility" this is by far the most used word in economics. You'll hear it from your first intro class to your phd asset pricing program. It doesn't mean anything super fancy, or something that must be "utilized" it's merely the measurement for someone's happiness. That's it! Nothing fancy at all just think that if I'm happier I'm getting more utility.  A variation that different professors might use are "welfare" it's pretty much the same thing and has nothing to do with food stamps.
Next is one that will confuse even the brightest graduate students. Some economists might say a phrase like "stochastic dynamic general equilibrium" when referring to some sort of economic activity. To explain it I'll break it down.
Stochastic means random. Some of you that are physicists might have heard of stochastic calculus and it sort of has the same meaning here.
Dynamic just means that things change.
And general equilibrium is basically where it all ends up. 
An analogy that I heard yesterday from David Zetland (who has his own blog here) was soccer.
The stochastic part are the random things that happen in the game.
The dynamics come in when because a player did something another player is going to do something. And if the first player had done something different then the second player would have done something different too. 
General equilibrium is where it ends up being whether it's 0-0, 1-2 or whatever the score is. 
So next time someone asks you if you know what stochastic dynamic general equilibrium means just say "yeah it's like soccer".
Optimization is also something you may hear in your intro classes. It the process of achieving your maximum utility.It can also be called acting optimally. 
Marginal is one that every economist should know. It's like a physicist not knowing the definition of mass. It just basically means adding one more of something. An extra unit of output or an extra hour of studying. It can mean adding another of anything. 
There are other words that get used a lot as well. Such as interest rates, money, discounting. These are for more specific economists so I won't articulate them here. 
If there is anything else you think I should mention feel free to write a comment.