To “emigrate” is to leave a country. The E at the beginning of the word is related to the E in other words having to do with going out, such as “exit.” “Immigrate,” in contrast, looks as if it might have something to do with going in, and indeed it does: it means to move into a new country. The same distinction applies to “emigration” and “immigration.” Note the double M in the second form. A migrant is someone who continually moves about.
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