Definition of expand
1 : to open up : unfold
2 : to increase the extent, number, volume, or scope of : enlarge
3a : to express at length or in greater detailb : to write out in full <expand all abbreviations>c : to subject to mathematical expansion <expand a function in a power series>
1 : to open out : spread
2 : to increase in extent, number, volume, or scope
3 : to speak or write fully or in detail <expanded on the theme>
4 : to feel generous or optimistic
expandabilityplay \ik-ˌspan-də-ˈbi-lə-tē\ noun
expandableplay \ik-ˈspan-də-bəl\ adjective
Examples of expand in a sentence
The liquid expands and contracts with changes in temperature.
His business has expanded to serve the entire state.
The coffee shop may expand into a full restaurant.
He has expanded his business to serve the entire state.
There are plans to expand the airport.
The police have decided to expand their investigation.
She plans to expand the lecture series into a book.
Expand the abbreviation “deg.” to “degree.”
Origin and Etymology of expand
Middle English expaunden, from Latin expandere, from ex- + pandere to spread — more at fathom
First Known Use: 15th century
Synonym Discussion of expand
EXPAND Defined for English Language Learners
Definition of expand for English Language Learners
: to increase in size, range, or amount : to become bigger
: to cause (something) to increase in size, range, or amount : to make (something) bigger
: to write (something) in full form
EXPAND Defined for Kids
Definition of expand for Students
1 : to grow or increase in size, number, or amount <The airport is expanding.>
2 : to open wide : unfold <The eagle's wings expanded.>
3 : to take up or cause to take up more space <Metals expand under heat.>
4 : to speak or write about in greater detail <Would you expand on that idea?>
Seen and Heard
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