migration

American  

[mahy-grey-shuhn] / maɪˈgreɪ ʃən /

noun

1. the process or act of migrating.

2. a migratory movement.

   preparations for the migration.

3. a number or body of persons or animals migrating together.

4. Chemistry. a movement or change of position of atoms within a molecule.

5. Physics. diffusion.

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migration British  

/ maɪˈɡreɪʃən /

noun

1. the act or an instance of migrating

2. a group of people, birds, etc, migrating in a body

3. chem a movement of atoms, ions, or molecules, such as the motion of ions in solution under the influence of electric fields

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migration Scientific  

/ mī-grā′shən /

1. The seasonal movement of a complete population of animals from one area to another. Migration is usually a response to changes in temperature, food supply, or the amount of daylight, and is often undertaken for the purpose of breeding. Mammals, insects, fish, and birds all migrate. The precise mechanism of navigation during migration is not fully understood, although for birds it is believed that sharp eyesight, sensibility to the Earth's magnetic field, and the positions of the Sun and other stars may play a role.

2. The movement of one atom or more, or of a double bond, from one position to another within a molecule.

3. The movement of ions between electrodes during electrolysis.

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Other Word Forms

• migrational
  adjective
• nonmigration
  noun
• premigration
  adjective
• remigration
  noun

Etymology

Origin of migration

First recorded in 1605–15, migration is from the Latin word migrātīon- (stem of migrātiō ). See migrate, -ion

Explanation

Migration is the movement of either people or animals from one area to another. Look up in the trees, where you might see a Monarch butterfly make a stop on its migration to Mexico. Migration can be used for the journey from one place to another or for the act of movement. Thousands of mid-western farmers made the migration to California during the dust bowl. Demographers have noted the migration of young people to the big cities presumably for work. With animals, it’s almost always in reference to a seasonal change in location. On boat tours, you can see the whales during their annual migration down the West coast.

Example Sentences

Even so, Muzaffar Chishti of the Migration Policy Institute said that the executive branch has vast discretion in immigration law, particularly when invoking national security justifications, and defense attorneys may face an uphill battle.

From Los Angeles Times • May 1, 2026

Migration to the U.K. jumped in the years after the Covid-19 pandemic, but fell sharply last year.

From The Wall Street Journal • Apr. 28, 2026

Migration typically unfolded slowly over generations and blended into everyday life, making it difficult to detect in standard burial grounds.

From Science Daily • Apr. 23, 2026

"Obtaining a residence permit in the European Union is not a blank cheque," Magnus Brunner, the Commissioner for Internal Affairs and Migration, told the European Parliament as Spain's initiative was being discussed.

From BBC • Mar. 8, 2026

Historians would come to call it the Great Migration.

From "The Sense of Style" by Steven Pinker

Related Words

• exodus
• flight
• journey
• movement
• shift
• transfer