al·​ter | \ ˈȯl-tər How to pronounce alter (audio) \
altered; altering\ ˈȯl-​t(ə-​)riŋ How to pronounce altering (audio) \

Definition of alter

transitive verb

1 : to make different without changing into something else an event that altered the course of history
2 : castrate, spay had the puppies altered

intransitive verb

: to become different customs that alter with the times

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Other Words from alter

alterability \ ˌȯl-​t(ə-​)rə-​ˈbi-​lə-​tē How to pronounce alterability (audio) \ noun
alterable \ ˈȯl-​t(ə-​)rə-​bəl How to pronounce alterable (audio) \ adjective
alterably \ ˈȯl-​t(ə-​)rə-​blē How to pronounce alterably (audio) \ adverb
alterer \ ˈȯl-​tər-​ər How to pronounce alterer (audio) \ noun

Choose the Right Synonym for alter

change, alter, vary, modify mean to make or become different. change implies making either an essential difference often amounting to a loss of original identity or a substitution of one thing for another. changed the shirt for a larger size alter implies a difference in some particular respect without suggesting loss of identity. slightly altered the original design vary stresses a breaking away from sameness, duplication, or exact repetition. vary your daily routine modify suggests a difference that limits, restricts, or adapts to a new purpose. modified the building for use by the disabled

Examples of alter in a Sentence

Alcohol can alter a person's mood. He altered his will to leave everything to his sister. This one small event altered the course of history. The place has altered in the 10 years since I left. I'll need to have the dress altered before the wedding.
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Recent Examples on the Web The governor’s office has distributed a checklist to day cares for reopening to all parents, including safety measures, altered drop-off and pick-up procedures and new rules for class sizes. Dallas News, "‘They’re forcing us into bankruptcy’: Day care owners say reopening orders are too little, too late for struggling businesses," 19 May 2020 For instance, federal officials last year proposed altering Obama-era regulations that require nursing homes to employ at least a part-time infection-control specialist., "Nursing Homes Face Catastrophic Mix of Virus and Lax Oversight," 19 May 2020 He was told the disease, along with his concussions, altered his brain chemistry. Eric Branch,, "Brain of Stanford standout Hoffpauir will be donated to noted CTE program," 18 May 2020 The precipitous drop came as people have drastically altered their purchase behavior. David Goldman, CNN, "Countries' massive debt piles are turning into a disaster," 17 May 2020 Carrying such tools might not be for everyone, though, so some 3D-printing evangelists have altered the design of the door itself. NBC News, "Knock-knock no more: Doors are being redesigned amid COVID-19," 17 May 2020 But the procedure goes awry, leaving Isabel (or Issy, as Jane calls her) grief-stricken and altered. Lucy Knisley, New York Times, "Carnival Performer, Newly Separated; Attachment Issues," 16 May 2020 For example, the money could go toward retrofitting the ventilation system of a grocery store to protect employees and shoppers or helping shops and restaurants alter building facades to allow for curbside pickup or social distancing. Rebekah L. Sanders, azcentral, "Arizona gets $21M more in federal housing assistance for COVID-19," 16 May 2020 McAnulty also pleaded guilty to destroying or altering physical evidence in the case. oregonlive, "Who’s on Oregon’s death row: 27 men; 2 others held elsewhere," 15 May 2020

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

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First Known Use of alter

14th century, in the meaning defined at transitive sense 1

History and Etymology for alter

Middle English alteren "to change, transform," borrowed from Anglo-French & Late Latin; Anglo-French alterer, borrowed from Late Latin alterāre, verbal derivative of Latin alter "second, another, next," derivative, with the suffix of opposition -ter-, from the base of alius "other" — more at else entry 1

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Time Traveler for alter

Time Traveler

The first known use of alter was in the 14th century

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Statistics for alter

Last Updated

22 May 2020

Cite this Entry

“Alter.” Dictionary, Merriam-Webster, Accessed 31 May. 2020.

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More Definitions for alter


How to pronounce alter (audio)

English Language Learners Definition of alter

: to change (something)
: to make a change to (a piece of clothing) so that it will fit better
US : to remove the sex organs of (an animal) so that the animal is unable to reproduce


al·​ter | \ ˈȯl-tər How to pronounce alter (audio) \
altered; altering

Kids Definition of alter

: to change partly but not completely … each time he had altered his course.— Walter Farley, The Black Stallion
al·​ter | \ ˈȯl-tər \
altered; altering\ -​t(ə-​)riŋ \

Medical Definition of alter

 (Entry 1 of 2)



Medical Definition of alter (Entry 2 of 2)

: one of the distinct identities or personality states manifested in an individual with multiple personality disorder

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More from Merriam-Webster on alter

Thesaurus: All synonyms and antonyms for alter

Rhyming Dictionary: Words that rhyme with alter

Spanish Central: Translation of alter

Nglish: Translation of alter for Spanish Speakers

Britannica English: Translation of alter for Arabic Speakers

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