expansion

noun

ex·​pan·​sion ik-ˈspan(t)-shən How to pronounce expansion (audio)
1
2
: the act or process of expanding
territorial expansion
economic expansion
expansion of the universe
3
: the quality or state of being expanded
4
: the increase in volume of working fluid (such as steam) in an engine cylinder after cutoff or in an internal combustion engine after explosion
5
a
: an expanded part
b
: something that results from an act of expanding
the book is an expansion of a lecture series
6
: the result of carrying out an indicated mathematical operation : the expression of a function in the form of a series
expansional adjective

Examples of expansion in a Sentence

The league is undergoing expansion. the expansion of a lecture series into a book This book is an expansion of a lecture series.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
When scaling disbursed teams, considerations include attracting and retaining the best talent to drive expansion. Expert Panel®, Forbes.com, 23 May 2025 The series, produced by BBC Studios India Productions in collaboration with All3Media International, represents Prime Video India’s expansion into high-profile reality programming. Naman Ramachandran, Variety, 23 May 2025 SpaceX is moving ahead with expansion plans at Vandenberg Space Force Base, California, that will double its West Coast launch cadence and enable Falcon Heavy rockets to fly from California, Spaceflight Now reports. ArsTechnica, 23 May 2025 But Italian beef, the quintessential Chicago sandwich, remains at the top of the Buona menu — and its expansion plans. Robert Channick, Chicago Tribune, 23 May 2025 See All Example Sentences for expansion

Word History

First Known Use

1611, in the meaning defined at sense 1

Time Traveler
The first known use of expansion was in 1611

Browse Nearby Words

Cite this Entry

“Expansion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/expansion. Accessed 28 May. 2025.

Kids Definition

expansion

noun
ex·​pan·​sion ik-ˈspan-chən How to pronounce expansion (audio)
1
: the act of expanding
2
: the state of being expanded
3
: something expanded or a result of expanding
4
: the result of carrying out indicated mathematical operations
the expansion of (a + b)2 is a2 + 2ab + b2

Medical Definition

expansion

noun
ex·​pan·​sion ik-ˈspan-chən How to pronounce expansion (audio)
1
: the act or process of expanding
2
: the quality or state of being expanded

More from Merriam-Webster on expansion

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