"An expatriate (expat or sometimes ex-pat) is a person temporarily or permanently residing in another country and culture other than their own."
I found this in a couple of places on the web. I don't think we need to attach any special significance to the word, as has been suggested. I've never once considered that the word may contain any special meaning of privilege, it just says that the person is living in a different country than that of his or her birth. Seems to me that to take the meaning of expat from the definition I propose, which is pretty close to a literal meaning with no culturally emotional biases applied to it, any further is stretching a definition to include more than one concept. That's where we start running into problems. In this case, it may be a stereotyping issue. The stereotype of the person who thinks he's better than anyone else just because he came from a certain country.
Quite frankly, many of us already have a problem of some perceiving this in us, because we complain about things here AND we're expats. So many people seem to think complaints mean superiority as well - I hope that's not another stretch that's trying to be made. I know what I think and how I feel, and it isn't superior. The feeling is, however, often frustrated. A very big difference.
For example, under this definition for expat, my wife, who is Paraguayan, is an expat. She is also considered an immigrant by the State here in Argentina (to answer bajo_cero's interjection - though the State's is not the only definition that can or should be applied to a person) because she has permanent residency here. She comes from a poor country. I don't think applying the word expat to her indicates a position of superiority; in fact, her position here is considered pretty low in some Argentines' eyes simply because she is an expat from another poor country.
I used to work in the oil field in Houston and we had many Europeans, Indians (Indian Indians, not "American Indians" - though I reckon we probably had an American Indian or two in the mix somewhere), Chinese, Vietnamese, German, Dutch, Norwegian, French, British, Italian and so on, ad infinitum, working in the States with us. They were all considered expats by us (as we considered ourselves "locals") and they considered themselves expats as well. Some had lived for many years in the States and had green cards Some felt superior, some actually were in many ways (usually not the way they thought!).
Expatriates are very simply people who came from another country and are currently living in another. Period.
If an expatriate wants to feel like there's some kind of special superiority, being "above the natives" or something, that's a personal problem and has nothing to do with the label he or she considers appropriate. They'll act like an ass anyway.
I'm an expat, an expatriate. So're my wife and my sister-in-laws. So are the two young ladies who go to English class with my wife, from Colombia and Peru. We're all the same. We're also immigrants, though not citizens. And one day we may well emigrate to Paraguay where my wife and sisters-in-law will be citizens...
...but I'll still be an expat.