verb ex·pand \ ik-ˈspand \
|Updated on: 14 Jul 2018

Definition of expand

expanded; expanding; expands
1 : to open up : unfold
2 : to increase the extent, number, volume, or scope of : enlarge
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
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


play \ik-ˌspan-də-ˈbi-lə-tē\ noun


play \ik-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.”

Recent Examples of expand from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'expand.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of expand

Middle English expaunden, from Latin expandere, from ex- + pandere to spread — more at fathom

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 (such 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 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


verb ex·pand \ ik-ˈspand \

Definition of expand for Students

expanded; expanding
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?

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to hasten

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