Definition of expansion
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 (as steam) in an engine cylinder after cutoff or in an internal combustion engine after explosion
5a : an expanded partb : 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
expansionalplay \ik-ˈspanch-nəl, -ˈspan(t)-shə-nəl\ 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.
First Known Use of expansion
EXPANSION Defined for English Language Learners
Definition of expansion for English Language Learners
: the act of becoming bigger or of making something bigger : the act of expanding
: a more complete and detailed written work or set of comments based on something shorter
EXPANSION Defined for Kids
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