al·​ter·​a·​tion | \ ˌȯl-tə-ˈrā-shən How to pronounce alteration (audio) \
plural alterations

Definition of alteration

1 : the act or process of altering something The dress needs alteration for a proper fit. : the state of being altered
2 : the result of changing or altering something: such as
a : a change made in fitting a garment no charge for alterations
b : a change in a legal instrument that alters its legal effect She made some alterations to her will.
c : a mineral that has been altered by a chemical process : metasomatism

Examples of alteration in a Sentence

the alteration of the pattern They did a good job on the dress alteration. He made alterations in his will.
Recent Examples on the Web Following Kafka’s lead, the cause of this sudden alteration remains unknown; its meaning is equally elusive. Ron Charles, Washington Post, 2 Aug. 2022 This allowed the researchers to test its behavior in various states of chemical alteration. John Timmer, Ars Technica, 27 Apr. 2022 This means the information cannot be tampered with, as network nodes continuously cross-check the information and can detect signs of alteration or tampering. Gary Fowler, Forbes, 26 Apr. 2022 The playwright has made substantial changes in the script, among them a reduction of more than 20 minutes in the running time and a pivotal alteration of place. Washington Post, 28 Jan. 2022 Even minor changes, such as a new shirt design or an alteration of a club crest, can be like grabbing soccer’s third rail. New York Times, 20 May 2022 The signs are that human alteration of global climate is driving the climate part of the equation. Joan Meiners, The Arizona Republic, 18 May 2022 In fact, alteration of sharp wave-ripple events by experimental manipulations or disease results in serious memory impairment [see graphic below]. György Buzsáki, Scientific American, 14 May 2022 Alexander tried to hide the alteration of his mechanics, a product of his elbow injury, from the coaching staff. Evan Petzold, Detroit Free Press, 4 May 2022 See More

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

First Known Use of alteration

14th century, in the meaning defined at sense 1

History and Etymology for alteration

Middle English alteracioun "change, transformation," borrowed from Anglo-French & Medieval Latin; Anglo-French alteracion, borrowed from Medieval Latin alterātiōn-, alterātiō, from Late Latin alterāre "to change, alter" + Latin -tiōn-, -tiō, suffix of verbal action

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

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Last Updated

11 Aug 2022

Cite this Entry

“Alteration.” Dictionary, Merriam-Webster, Accessed 16 Aug. 2022.

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More Definitions for alteration


al·​ter·​ation | \ ˌȯl-tə-ˈrā-shən How to pronounce alteration (audio) \

Kids Definition of alteration

1 : the act or process of changing something She began alteration of the design.
2 : the result of changing : modification a minor alteration

More from Merriam-Webster on alteration

Nglish: Translation of alteration for Spanish Speakers

Britannica English: Translation of alteration for Arabic Speakers


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