Definition of domino theory
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
Origin of domino theory
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
Learn More about domino theory
Britannica.com: Encyclopedia article about "domino theory"
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