[Xixi]

From an administrative perspective in the US an immigrant is someone who moves to the US with the intent of staying. Work and other temporary visas are called non-immigrant visas, and for example when I applied for my E-2 visa I had to clearly state that I had no intent to immigrate in the US (though I was applying to work in the US, I'm not an investor despite what the visa is called). As I fully intend to leave, I didn't have to lie about it.

Even in a more casual context, I know a lot of Japanese expats in US, and have never heard of any of them being called an immigrant: most come from one of the big Japanese banks (Mitsui Sumitomo, UFJ, etc.) and stay in NYC for two to five years, before heading back either to Japan. Cultural quirk: Japanese people are usually sent abroad right after purchasing a house in Japan, the management line of thought being that with the associated mortgage they won't quit even if they don't want to go abroad.