Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

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)

Word of the Day

handout

a document given to students or reporters which contains information about a particular subject

Word of the Day

Blog

Read our blog about how the English language behaves.

Learn More

New Words

Find words and meanings that have just started to be used in English, and let us know what you think of them.

Learn More