alter

verb

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

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
alterability noun
alterable adjective
alterably adverb
alterer 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.
Recent Examples on the Web At the destination wedding in Ireland, Maddie makes a wish that alters their fates — with comical results. Eric Andersson, Peoplemag, 16 Mar. 2024 But there were at least two reforms in the Pac-12 proposal that might have altered the trajectory of college sports had they been adopted a decade ago, according to Winter, Aresco and other industry experts who reviewed the reforms at the Hotline’s request but declined to comment. Jon Wilner, The Mercury News, 14 Mar. 2024 What happened in the early 2010s that altered adolescent development and worsened mental health? Jonathan Haidt, The Atlantic, 13 Mar. 2024 This suspension takes advantage of the onboard high-voltage system in the plug-in hybrids to power four pumps, one per corner, which can almost immediately alter the suspension at every corner—on the fly. Tim Stevens, Robb Report, 13 Mar. 2024 Recent research suggests an additional way salt may raise blood pressure – by altering your gut microbiome. Christopher Damman, The Conversation, 12 Mar. 2024 There is no evidence they’ve been manipulated to alter the results of an election. Katie Bernard, Kansas City Star, 5 Mar. 2024 And this story isn’t about about the recent storms, but Hayley also wrote about new research warning that with climate change, a crucial ocean current could collapse, altering global weather. Sammy Roth, Los Angeles Times, 5 Mar. 2024 Her disappearance altered practices and people. March 3, 2024 at 6:00 a.m. Ellie Silverman, Washington Post, 3 Mar. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'alter.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

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

First Known Use

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

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

Dictionary Entries Near alter

Cite this Entry

“Alter.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/alter. Accessed 28 Mar. 2024.

Kids Definition

alter

verb
al·​ter ˈȯl-tər How to pronounce alter (audio)
1
: to change partly but usually not completely
alter a dress
2
alterability noun
alterable adjective
alterer noun
Etymology

Middle English alteren "to make different," from Latin alterare (same meaning), from Latin alter "other (of two)" — related to adulterate

Medical Definition

alter

1 of 2 transitive verb
al·​ter
ˈȯl-tər
altered; altering
-t(ə-)riŋ

alter

2 of 2 noun
: one of the distinct identities or personality states manifested in an individual with dissociative identity disorder

More from Merriam-Webster on alter

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