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verb ex·pand \ik-ˈspand\

Simple Definition of expand

  • : 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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of expand

  1. transitive verb
  2. 1 :  to open up :  unfold

  3. 2 :  to increase the extent, number, volume, or scope of :  enlarge

  4. 3 a :  to express at length or in greater detail b :  to write out in full <expand all abbreviations> c :  to subject to mathematical expansion <expand a function in a power series>

  5. intransitive verb
  6. 1 :  to open out :  spread

  7. 2 :  to increase in extent, number, volume, or scope

  8. 3 :  to speak or write fully or in detail <expanded on the theme>

  9. 4 :  to feel generous or optimistic

expandability play \-ˌspan-də-ˈbi-lə-tē\ noun
expandable play \-ˈspan-də-bəl\ adjective

Examples of expand in a sentence

  1. The liquid expands and contracts with changes in temperature.

  2. His business has expanded to serve the entire state.

  3. The coffee shop may expand into a full restaurant.

  4. He has expanded his business to serve the entire state.

  5. There are plans to expand the airport.

  6. The police have decided to expand their investigation.

  7. She plans to expand the lecture series into a book.

  8. Expand the abbreviation deg. to degree.

Origin 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, amplify, swell, distend, inflate, dilate mean to increase in size or volume. expand may apply regardless of the manner of increase (as growth, unfolding, addition of parts) <a business that expands every year>. amplify implies the extension or enlargement of something inadequate <amplify the statement with details>. swell implies gradual expansion beyond a thing's original or normal limits <the bureaucracy swelled to unmanageable proportions>. distend implies outward extension caused by pressure from within <a distended abdomen>. inflate implies expanding by introduction of air or something insubstantial and suggests a vulnerability to sudden collapse <an inflated ego>. dilate applies especially to expansion of circumference <dilated pupils>.

EXPAND Defined for Kids


verb ex·pand \ik-ˈspand\

Definition of expand for Students


  1. 1 :  to grow or increase in size, number, or amount <The airport is expanding.>

  2. 2 :  to open wide :  unfold <The eagle's wings expanded.>

  3. 3 :  to take up or cause to take up more space <Metals expand under heat.>

  4. 4 :  to speak or write about in greater detail <Would you expand on that idea?>

Seen and Heard

What made you want to look up expand? Please tell us where you read or heard it (including the quote, if possible).


the range of perception or understanding

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