containment

American  

[kuhn-teyn-muhnt] / kənˈteɪn mənt /

noun

1. the act or condition of containing.

2. an act or policy of restricting the territorial growth or ideological influence of another, especially a hostile nation.

3. an act or policy of limiting the expansion or spread of a natural disaster, contagious disease, or other dangerous thing: Local farmers notified authorities of sick and dying birds more quickly than the previous year, ensuring quick containment of infection on the farm.

   Containment of the wildfire reached nearly 40% before powerful winds carried embers over the perimeter, reducing containment.

   Local farmers notified authorities of sick and dying birds more quickly than the previous year, ensuring quick containment of infection on the farm.

4. (in a nuclear power plant) an enclosure completely surrounding a nuclear reactor, designed to prevent the release of radioactive material in the event of an accident.

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containment British  

/ kənˈteɪnmənt /

noun

1. the act or condition of containing, esp of restraining the ideological or political power of a hostile country or the operations of a hostile military force

2. (from 1947 to the mid-1970s) a principle of US foreign policy that sought to prevent the expansion of Communist power

3. Also called: confinement.  physics the process of preventing the plasma in a controlled thermonuclear reactor from reaching the walls of the reaction vessel, usually by confining it within a configuration of magnetic fields See magnetic bottle

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containment Cultural  

1. A policy aimed at controlling the spread of communism around the world, developed in the administration of President Harry S. Truman. The formation of the North Atlantic Treaty Organization (NATO) in 1949 was an important step in the development of containment.

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Etymology

Origin of containment

First recorded in 1645–55; contain + -ment

Explanation

Containment is a way to keep something bad from spreading. If you get chicken pox, you won't be allowed back in school until you're not contagious anymore. Your school's aiming for containment of the disease by keeping you away from everyone else. Containment is also a foreign policy strategy. If one country is stirring up trouble by sending weapons and fighters into neighboring countries, other countries can join together and enact a policy of containment, to isolate the rogue country and keep it from causing chaos outside its borders. In a nuclear reactor, the containment system is the back-up system that's supposed to keep dangerous radiation from leaking out into the atmosphere or water when there's an accident.

Example Sentences

The public health measures announced Monday will include continued "deployment of CDC personnel to support outbreak containment efforts in affected regions" as well as assistance with contact tracing and laboratory testing, the agency said.

From Barron's • May 18, 2026

The unit originated many infection containment and personal protective equipment practices that are now standard across medicine today.

From Slate • May 14, 2026

“This is no longer just about containment; it is about testing the pathway to resolution.”

From MarketWatch • May 5, 2026

Competition lowers costs through a competitive bidding process and by providing cost containment measures to prevent price escalation during the construction process.

From The Wall Street Journal • Mar. 4, 2026

They assumed that the torus had ruptured—meaning that the containment vessel for the reactor had been breached.

From "Meltdown" by Deirdre Langeland

Related Words

• authority
• curb
• discipline
• domination
• force
• government
• jurisdiction
• management
• oversight
• regulation
• restraint
• restriction
• rule
• supervision