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 Earlier this year, Trump signed the U.S.-Mexico-Canada Agreement, dubbed the USMCA, as part of fulfilling his key 2016 campaign promise to alter free trade agreements that put the U.S. at an economic disadvantage. Anthony Leonardi, Washington Examiner, "Trudeau declines White House invitation to celebrate new trade deal amid coronavirus," 6 July 2020 Social distancing and the ability of many employees to work from home are factors that could alter real estate needs for businesses. Russ Wiles, The Arizona Republic, "How commercial real estate in metro Phoenix is faring during COVID-19 pandemic," 4 July 2020 But the question academics, experts and other stakeholders are now asking is: How permanently and severely will the commercial space race alter the night sky? Jackie Wattles, CNN, "How Elon Musk's Starlink satellites may have stifled the best chance to find Planet 9," 2 July 2020 Experts say its provisions fundamentally alter the legal landscape in Hong Kong, carving out space within the city’s Western-style rule-of-law system for mainland... Chun Han Wong, WSJ, "What’s in Hong Kong’s New National-Security Law," 2 July 2020 This week, however, neighboring states are contemplating ideas that could alter their seasons substantially. Ben Thomas |, al, "Alabama, other states still face tough questions about 2020 high school football season," 1 July 2020 While all looks promising on the immediate front, Psencik said the July 14 meeting could alter the fall outlook. Ted Dunnam, Houston Chronicle, "Lutheran South, Bay Area Christian remain hopeful for fall sports," 1 July 2020 Arguably, this move is less about helping the game's developers alter and upgrade the game's contents and more about changing the way outsiders view its tiny player population. Sam Machkovech, Ars Technica, "Amazon’s latest PC game to be delisted from Steam after less than two months," 30 June 2020 In a show of unity and force, multiple University of Texas athletes from various sports posted a series of requests on social media Friday that, if enacted, would radically alter the racial landscape at the school. Brian Davis, USA TODAY, "Texas athletes call for changes to address university's racial past and future," 12 June 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

27 Jul 2020

Cite this Entry

“Alter.” Dictionary, Merriam-Webster, Accessed 3 Aug. 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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