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

A major factor in 2025’s population trends was a sharp drop in net international migration.

From Los Angeles Times • May 6, 2026

“There’s a reason why we have a good reputation,” said Chris Ross, vice president of migration and refugee resettlement services at Catholic Charities.

From Salon • May 2, 2026

With stronger market sentiment lifting demand deposits, Ping An Bank is well-placed to benefit from deposit migration given its retail banking strength and ties to parent Ping An Insurance, Morningstar adds.

From The Wall Street Journal • Apr. 29, 2026

The answer lies in a process called "radial migration" -- stars gradually moving outward from their birthplaces by interacting with spiral waves in the Galaxy.

From Science Daily • Apr. 29, 2026

Other ethologists are interested in a particular kind of behavior, such as the migration of birds.

From "My Life with the Chimpanzees" by Jane Goodall

Related Words

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