migration Meaning, Definition & Usage

1. noun the movement of persons from one country or locality to another
   
2. noun a group of people migrating together (especially in some given time period)
   
3. noun (chemistry) the nonrandom movement of an atom or radical from one place to another within a molecule
   
4. noun the periodic passage of groups of animals (especially birds or fishes) from one region to another for feeding or breeding
   

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