expansion
noun
ex·pan·sion
ik-ˈspan(t)-shən 
1
: expanse
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
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
In his eastern Connecticut district, Courtney landed $2 million for the Connecticut Department of Housing to help with the expansion of affordable housing at Country Place in Colchester to rehabilitate 194 units of family housing.
—
Lisa Hagen, Hartford Courant, 13 Feb. 2026
The redevelopment will include an expansion of the community’s existing Meadows apartment complex with a new wing that will have 47 residences.
—Nathan Pilling, Kansas City Star, 13 Feb. 2026
New York City’s most famous bagels are coming to Pinecrest as part of the brand’s expansion into Florida.
—Connie Ogle, Miami Herald, 13 Feb. 2026
Lowe’s also detailed its plans for further expansion with a wave of new stores debuting over the next few years.
—Charlotte Observer, 13 Feb. 2026
See All Example Sentences for expansion
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.
Lisa Hagen, Hartford Courant, 13 Feb. 2026
The redevelopment will include an expansion of the community’s existing Meadows apartment complex with a new wing that will have 47 residences.
—Nathan Pilling, Kansas City Star, 13 Feb. 2026
New York City’s most famous bagels are coming to Pinecrest as part of the brand’s expansion into Florida.
—Connie Ogle, Miami Herald, 13 Feb. 2026
Lowe’s also detailed its plans for further expansion with a wave of new stores debuting over the next few years.
—Charlotte Observer, 13 Feb. 2026
See All Example Sentences for expansion
Cite this Entry
“Expansion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/expansion. Accessed 14 Feb. 2026.
Copy CitationKids Definition
expansion
noun
ex·pan·sion
ik-ˈspan-chən
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
Love words? Need even more definitions?
Merriam-Webster unabridged
