(n): the act of changing location from one place to another
(n): a group of people migrating together (especially in some given time period)
(n): (plural) any group of human beings (men or women or children) collectively
(n): (chemistry) the nonrandom movement of an atom or radical from one place to another within a molecule
(n): something that happens at a given place and time
(n): the periodic passage of groups of animals (especially birds or fishes) from one region to another for feeding or breeding
(n): an event that recurs at intervals
