ad·​den·​dum | \ə-ˈden-dəm \
plural addenda\-​ˈden-​də \ 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

There is a classified addendum to the Justice OIG report, so the full extent of the evidence considered in the Clinton investigation may not be known for decades. Sean Gallagher, Ars Technica, "FBI refutes Trump claim that Clinton’s private email server was hacked by China," 29 Aug. 2018 An addendum released Tuesday includes the names of three additional people who allegedly committed abuse between 1967 and 1988. Michael Casey, The Seattle Times, "Prep school details more cases of sex abuse by ex-faculty," 21 Aug. 2018 Life comes with addendums, and mine is a condition called hyperhidrosis. Rachel Nussbaum, Glamour, "How I Finally Gave In and Became a Sneaker Person," 8 Aug. 2018 Oregon recently approved an addendum to its building code that allows timber structures to be built over six stories without having to acquire special permission. Liz Stinson, Curbed, "The state is the first in the U.S. to legalize mass timber high rises," 21 Aug. 2018 Yesterday’s addendum mentioned the growing likelihood of an extended heat wave over the eastern United States during the first week of July. Greg Porter, Washington Post, "PM Update: Scattered showers early, clearing overnight. Warm and comfortable on Monday.," 24 June 2018 On May 15, the board unanimously passed a second addendum removing the residential requirement. Alexandra Kukulka,, "Village manager does not have to move to Glenview following board vote," 22 May 2018 Indeed, in the hunter-gatherer hierarchy, the rewards of hunting have always taken precedence over those of gathering: Meat is a main course and vegetables an addendum, even in our current phase of celebrating crudités. Ligaya Mishan, New York Times, "The Golden Age of Crudités," 8 Feb. 2018 Since the Committee introduced short-term rental restrictions in a 2016 addendum, Property Compliance Manager Neslihan Tesno said, six people have applied and all of them have had their applications rejected. Marialuisa Rincon, Houston Chronicle, "Township officials face challenges with Airbnb," 8 July 2018

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

4 Dec 2018

Look-up Popularity

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 \
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).


a soft lustrous wool fabric with mohair

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