ad·​den·​dum | \ ə-ˈden-dəm How to pronounce addendum (audio) \
plural addenda\ -​ˈden-​də How to pronounce addenda (audio) \ also addendums

Definition of addendum

1 : a thing added : addition
2 : a supplement to a book often used in plural but singular in construction

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Synonyms & Antonyms for addendum


afterword, appendix, codicil, excursus, supplement


foreword, introduction, preface, prologue (also prolog)

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Examples of addendum in a Sentence

Francine du Plessix Gray, in an essay first written in 1991 and updated with an addendum here, writes eloquently of a lifelong obsession with weight loss, stemming from the harsh judgments of a mother enraptured by fashion. — Ginia Bellafante, New York Times Book Review, 21 Sept. 2008 This qualification, however, is not a recent addendum to Derrida's career. In 1990, near the end of the period in which rhetoric and composition had a strong interest in his work, Derrida participated in an editor's interview … in which he characterized his project as fundamentally tied to the tradition it works both within and against. College English, September 2006 The letters are included as an addendum to the biography. there's an addendum from the author to explain certain stylistic choices that she made
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Recent Examples on the Web

In his addendum to Rambam’s (Maimonides) Book of Commandments, Ramban notes that Rambam failed to mention living in Israel as a distinct mitzvah. Rabbi Avi Weiss,, "The value of living in the land of Israel," 29 July 2019 That said, Lieu was effective in his ability to succinctly paint a picture of how Trump obstructed justice and what factors stifle his prosecution (Mueller later added an addendum at the second hearing). Michael Arceneaux, Essence, "Opinion: Will Nancy Pelosi Finally Do Something About Donald Trump’s Abuse Of Power?," 25 July 2019 Refusing to concede, Trump had insisted his administration push forward, suggesting last week that officials might be able to add an addendum to the questionnaire with the question after it’s already printed. Mark Sherman,, "Trump abandons effort to put citizenship question on 2020 Census, will pursue other ways to get data," 11 July 2019 View Sample Sign Up Now Trump suggested the question could be included as an addendum if it were approved later. Mahita Gajanan, Time, "Trump Administration Tells Court It Will Push Ahead With Efforts to Add Citizenship Question To Census," 5 July 2019 An addendum stated A Second Look owed nearly $90,000 to consigners and more than $440,000 in loans and credit-card debt. Rebekah Sanders, azcentral, "'Why wouldn't they give us the money?' Phoenix store owes consigners thousands," 20 June 2019 Tacking on the citizenship question through an addendum is also fraught with legal and practical risks. John Wagner,, "Government lawyers step up effort to get a citizenship question on 2020 Census, court filing shows," 5 July 2019 Indeed, this small addendum to his messaging would be potent and serve as the best rebuttal to claims that his policy proposals—such as Medicare for All and eliminating student debt—are unrealistic. Adam Eichen, The New Republic, "Restoring Democracy is Not Open to Debate," 2 July 2019 The central bank releases its new policy statement at 2 p.m. EDT along with updated economic projections and any potential addendum to its balance sheet plans. Nick Timiraos, WSJ, "Fed, Facing Pressure on Rate Cut, to Decide on Next Move," 19 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'addendum.' 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 addendum

1664, in the meaning defined at sense 1

History and Etymology for addendum

borrowed from Latin, neuter of addendus, gerundive of addere "to add"

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Statistics for addendum

Last Updated

14 Aug 2019

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Time Traveler for addendum

The first known use of addendum was in 1664

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More Definitions for addendum



English Language Learners Definition of addendum

: something that is added especially : a section of a book that is added to the main or original text


ad·​den·​dum | \ ə-ˈden-dəm How to pronounce addendum (audio) \
plural addenda\ ə-​ˈden-​də \

Kids Definition of addendum

: something added (as to a book)

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Comments on addendum

What made you want to look up addendum? Please tell us where you read or heard it (including the quote, if possible).


to move or obtain by small maneuvers

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