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

Or in your appendix? There is even a cancer of the heart. Farhad Manjoo, New York Times, "Farhad’s Week in Tech: Bitcoin and the Scams Under Everything," 15 June 2018 Avicii had canceled tour dates in 2014 after having his gall bladder and appendix removed, and had been hospitalized twice in the preceding two years for acute pancreatitis, according to Billboard. The Washington Post,, "Avicii, struggling with health and fame, tried to walk away from it all two years before he died," 21 Apr. 2018 Timelines in an appendix anchor the reader in these plots, but the book’s chronology is more cyclical than linear. Gaiutra Bahadur, New York Times, "She Didn’t Know How to Read, but Her Stories Captured History," 10 May 2018 When not promptly and properly treated, the appendix can rupture. Lindsey Bever, Washington Post, "In case you missed the ‘condom-snorting challenge’ — and didn’t know it’s a bad idea," 2 Apr. 2018 When not promptly and properly treated, according to the Mayo Clinic, the appendix can rupture. Lindsey Bever,, "The ‘condom-snorting challenge’ is sweeping social media. Experts say it’s a bad idea," 2 Apr. 2018 The famous magician, illusionist, and entertainer definitely died from peritonitis caused by a ruptured appendix, but the real reason for his death is a mystery due to multiple contradicting reports. Lauren Smith, Good Housekeeping, "18 Fascinating Things You Didn't Know About Halloween," 7 July 2018 Published by local boutique house David R. Godine, Inc., this hefty, handsome two-volume set includes expertly typeset scores, many illustrations, and a comprehensive appendix of commentary on the music and composers as well as a companion CD. Jeremy Eichler And Zoë Madonna,, "Summer reading for the ears," 21 June 2018 Having your appendix removed, for example, can cost anywhere from $1,500 to $183,000, depending on the insurer. The Economist, "Land of the free-for-allAmerica is a health-care outlier in the developed world," 26 Apr. 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

15 Oct 2018

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

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


noxious or harmful

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