[1] : The Collaborative International Dictionary of English v.0.48

immigration \im"migra"tion\, n. cf. f. immigration.
   the act of immigrating; the passing or coming into a country
   for the purpose of permanent residence.
   1913 webster

         the immigrations of the arabians into europe. --t.
                                                  warton.
   1913 webster

[2] : WordNet (r) 2.0

immigration
     n 1: migration into a place especially migration to a country of
          which you are not a native in order to settle there
          syn: in-migration
     2: the body of immigrants arriving during a specified interval;
        "the increased immigration strengthened the colony"
see also:
in-migration 

[3] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

immigration. the removing into one place from another. it differs from 
emigration, which is the moving from one place into another. vide 
emigration. 

Immigration >> I Words
Immigration, definition of term: Immigration
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