Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English


English definition of “boom”


noun [C or U] (PERIOD OF GROWTH)    /buːm/
a period of sudden economic growth , especially one that results in a lot of money being made: This year has seen a boom in book sales . The insurance business suffered from a vicious cycle of boom and bust . the property boomEconomics and the state of the economySuccess and achievementsHigher and lower points of achievementFailures
(Definition of boom noun (PERIOD OF GROWTH) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
Focus on the pronunciation of boom

Definitions of “boom” in other dictionaries

Word of the Day

best man

a male friend or relation of the bridegroom who stands with him and helps him during a marriage ceremony

Word of the Day


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