ap·​pen·​dix | \ ə-ˈpen-diks \
plural appendixes or appendices\ -​də-​ˌsēz \

Definition of appendix

1a : appendage
b : supplementary material usually attached at the end of a piece of writing The book's appendix includes a bibliography.
2 : a bodily outgrowth or process specifically : vermiform appendix

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Synonyms & Antonyms for appendix


addendum, afterword, codicil, excursus, supplement


foreword, introduction, preface, prologue (also prolog)

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Examples of appendix in a Sentence

In your textbooks, turn to Appendix 3: Glossary of Terms. The book has several appendixes .

Recent Examples on the Web

The results from Finland contradict decades of thinking about the best way to treat an inflamed appendix. Fox News, "Pills for appendicitis? Surgery often not needed, study says," 25 Sep. 2018 Three technical appendices cover the geological time scale, the durations and rates of earthly phenomena, and the history of Earth’s environmental crises, including five mass extinctions. Robert M. Thorson, WSJ, "‘Timefulness’ Review: Thinking in Eons," 30 Dec. 2018 In the end, Starr and his team at the Office of the Independent Counsel sent a 453-page report (plus 2,000 pages of appendixes) to Congress, 20 years ago Tuesday. Dan Zak, The Seattle Times, "The Starr Report got a president impeached 20 years ago, and Ken Starr wants to remind you why," 11 Sep. 2018 That takes diligence: being the one who reads the whole report, the one who checks the appendix, the one who makes the extra call, the one who gets some extra background from podcasts or recorded lectures while doing the dishes or walking the dog. David Roberts, Vox, "My advice for aspiring explainer journalists," 9 Dec. 2018 About one-third had another case of appendicitis and had surgery to take out their appendix. Fox News, "Pills for appendicitis? Surgery often not needed, study says," 25 Sep. 2018 Existence of this classified appendix has gone virtually unmentioned in the media. Holman W. Jenkins, WSJ, "New Hope for the Truth of 2016?," 16 Nov. 2018 Emily Bell had the idea of adding letters from Berlin’s correspondence as an appendix to the memoir. Bridget Read, Vogue, "How Lucia Berlin Became A Literary Superstar 11 Years After Her Death (And Is About to Publish A New Collection)," 5 Nov. 2018 Ignored is even the secret appendix to the Justice Department’s own damning review of Mr. Comey’s actions. Holman W. Jenkins, WSJ, "America Has Yet to Make Sense of Trump," 19 Oct. 2018

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

1542, in the meaning defined at sense 1a

History and Etymology for appendix

Latin appendic-, appendix, from appendere — see append

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Statistics for appendix

Last Updated

5 Feb 2019

Look-up Popularity

Time Traveler for appendix

The first known use of appendix was in 1542

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More Definitions for appendix



English Language Learners Definition of appendix

: a section of extra information added at the end of a book
: a small tube at the beginning of the large intestine that can be removed by surgery if it becomes infected


ap·​pen·​dix | \ ə-ˈpen-diks \
plural appendixes or appendices\ -​də-​ˌsēz \

Kids Definition of appendix

1 : a part of a book giving added and helpful information (as notes or tables)
2 : a small tubelike part growing out from the large intestine


ap·​pen·​dix | \ ə-ˈpen-diks \
plural appendixes or appendices\ -​də-​ˌsēz \

Medical Definition of appendix

: a bodily outgrowth or process specifically : vermiform appendix

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Comments on appendix

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