n.
1.the movement of persons from one country or locality to another
2.a group of people migrating together (especially in some given time period)
3.(chemistry) the nonrandom movement of an atom or radical from one place to another within a molecule
4.the periodic passage of groups of animals (especially birds or fishes) from one region to another for feeding or breeding
Idiom of the Day
dress (someone) down or dress down (someone)
to scold someone
The supervisor took the clerk into her office to dress her down.