Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English


English definition of “expansion”


noun [C or U]     /ɪkˈspæn.ʃən/
B2 the increase of something in size, number, or importance: the rapid expansion of the software industry Expansion into new areas of research is possible. an expansion of industryBecoming biggerEnlarging and inflating
(Definition of expansion noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
Focus on the pronunciation of expansion

Definitions of “expansion” in other dictionaries

Word of the Day

limber up

to do gentle exercises to stretch the muscles in order to prepare the body for more active physical exercise

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