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English definition of “domino theory”

domino theory

noun [C usually sing]  /ˈdɑm·ə·noʊ ˌθɪər·i, ˌθi·ə·ri/
politics & government a belief in the 1950s and 1960s that if one country became communist , other close countries would more easily also become Communist
(Definition of domino theory noun from the Cambridge Academic Content Dictionary © Cambridge University Press)

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