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Synonyms

alter

1 American  
[awl-ter] / ˈɔl tər /

verb (used with object)

  1. to make different in some particular, as size, style, course, or the like; modify.

    to alter a coat; to alter a will; to alter course.

  2. to castrate or spay.


verb (used without object)

  1. to change; become different or modified.

Alter 2 American  
[awl-ter] / ˈɔl tər /

noun

  1. David, 1807–81, U.S. physicist.


alter. 3 American  

abbreviation

  1. alteration.


alter British  
/ ˈɔːltə /

verb

  1. to make or become different in some respect; change

  2. informal (tr) a euphemistic word for castrate spay

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

What is another way to say alter?

To alter something is to make it different in some particular way, such as in size, style, or course. How does alter compare to change? Find out on Thesaurus.com.

Related Words

See adjust,

Other Word Forms

  • alterability noun
  • alterable adjective
  • alterably adverb
  • alterer noun
  • half-altered adjective
  • prealter verb (used with object)
  • realter verb
  • unaltering adjective
  • well-altered adjective

Etymology

Origin of alter

First recorded in 1350–1400; Middle English, from Old French alterer, from Late Latin alterāre “to change, worsen,” derivative of Latin alter “other”

Explanation

After eating too many gingerbread cookies, she no longer fit into her uniform, so she had a seamstress alter it. It looked pretty much the same. The verb alter can also mean to neuter or spay. Think of a cat that has just been spayed: the cat you pick up from the vet is the same cat that you dropped off there, only perhaps a little groggy and unable to reproduce. While the cat has been altered, it's not a different cat.

Keep Reading on Vocabulary.com

Vocabulary lists containing alter

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

It’s done at the state level, and Congress can legislate to alter the time, place, and manner of elections.

From Slate • Apr. 15, 2026

Instead, they would subtly alter the frequency of the emitted photons depending on the direction in which they travel.

From Science Daily • Apr. 10, 2026

Kay said she was also concerned about the presence of adverts on some newer, discounted Kindle devices, and how these might alter the reading experience.

From BBC • Apr. 9, 2026

It can also alter polar and tropical jet streams, sending storms on a path through Southern California and the southern United States, experts say.

From Los Angeles Times • Apr. 9, 2026

How silly she had been to think that time, distance, or anything else would ever alter her friendship with Miss Mortimer!

From "The Hidden Gallery" by Maryrose Wood