domino theory

noun

1
: a theory that if one nation becomes Communist-controlled the neighboring nations will also become Communist-controlled
2
: the theory that if one act or event is allowed to take place a series of similar acts or events will follow

Examples of domino theory in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
My father believed in the domino theory, how a cascade of Communism might deluge Asia. Hannah Beech, New York Times, 1 May 2025 This shock heightened Cold War fears of communist expansion and solidified the domino theory: the idea that if one state falls to communism, its neighbors will, too. Michael Beckley, Foreign Affairs, 7 Jan. 2025 The logic of the domino theory took on particular urgency in the early 1980s, after the collapse of the corrupt and brutal Somoza dynasty in Nicaragua and the coming to power of a Marxist-Leninist government—the Sandinistas, who in turn supported leftist guerrillas in neighboring El Salvador. TIME, 9 Aug. 2024 The Vietnam war discredited domino theories, e.g., if Ukraine falls, President Putin will invade and conquer all of Europe and maybe even the United States. Armstrong Williams, Baltimore Sun, 24 Mar. 2024 The domino theory had the Big 12 being one of the beneficiaries of a Pac-12 implosion. Dallas News, 19 Jan. 2023

Word History

Etymology

from the fact that if dominoes are stood on end one slightly behind the other, a slight push on the first will topple the others

First Known Use

1965, in the meaning defined at sense 1

Time Traveler
The first known use of domino theory was in 1965

Browse Nearby Words

Cite this Entry

“Domino theory.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/domino%20theory. Accessed 14 Sep. 2025.

Kids Definition

domino theory

noun
1
: a theory that if one nation becomes Communist-controlled the neighboring nations will also become Communist-controlled
2
: the theory that if one act or event is allowed to take place a series of similar acts or events will follow

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