appendix

[ uh-pen-diks ]

noun

, plural ap·pen·di·ces [uh, -, pen, -d, uh, -seez], ap·pen·dix·es.

1. supplementary material at the end of a book, article, document, or other text, usually of an explanatory, statistical, or bibliographic nature.

   Synonyms: addition, appurtenance, addendum, supplement, adjunct

2. an appendage.
3. Anatomy.
   1. a process or projection.
   2. the vermiform appendix.
4. Aeronautics. the short tube at the bottom of a balloon bag, by which the intake and release of buoyant gas is controlled.

appendix

/ əˈpɛndɪks /

noun

1. a body of separate additional material at the end of a book, magazine, etc, esp one that is documentary or explanatory
2. any part that is dependent or supplementary in nature or function; appendage
3. See vermiform appendix
   anatomy See vermiform appendix

appendix

/ ə-pĕn′dĭks /

, Plural appendixes ə-pĕn′-dĭ-sēz′

1. A tubular projection attached to the cecum of the large intestine and located on the lower right side of the abdomen.
2. Also called vermiform appendix

appendix

1. A small saclike organ located at the upper end of the large intestine . The appendix has no known function in present-day humans, but it may have played a role in the digestive system in humans of earlier times. The appendix is also called the vermiform appendix because of its wormlike (“vermiform”) shape.

Spelling Note

Appendices, a plural borrowed directly from Latin, is the usual plural, especially in scholarly writing, when referring to supplementary material at the end of a book. Appendixes is the usual plural in the anatomical meaning.

Word History and Origins

Origin of appendix¹

First recorded in 1535–45; from Latin: literally, “appendage,” equivalent to append(ere) “to add on” + -ix (equivalent to -ic- noun suffix + -s nominative singular ending); append

Word History and Origins

Origin of appendix¹

C16: from Latin: an appendage, from appendere to append

Synonym Study

Appendix, supplement both mean material added at the end of a book. An appendix gives useful additional information, but even without it the rest of the book is complete: In the appendix are forty detailed charts. A supplement, bound in the book or published separately, is given for comparison, as an enhancement, to provide corrections, to present later information, and the like: A yearly supplement is issued.

Example Sentences

Jones missed all but one game in the 1953-1954 season because of a ruptured appendix.

From Washington Post

Much of that data was included in the appendix to the report.

From Washington Post

An appendix published years later clarifying those federal rules, which more cleanly describe mobility challenges, states mental illnesses are not considered a disability under the federal transit rules.

From Voice of San Diego

The neighborhood updated its community plan in 2018 and devoted a whole appendix on planning for sea level rise.

From Voice of San Diego

When he was 12, his appendix burst and he underwent emergency surgery, followed by a desperate eight-hour ambulance ride to another hospital in search of better medication to stop the bleeding.

From MIT Technology Review

The longtime justice, appointed by President Clinton, added a lengthy appendix of evidence he found relevant to his dissent.

From The Daily Beast

Things go well until Oscar the Grouch is diagnosed with a burst appendix and Romney discovers he is uninsured.

From The Daily Beast

That appendix is taken more seriously because it is between the covers of a holy book.

From The Daily Beast

Comes with the funniest footnotes and appendix (no kidding) ever written.

From The Daily Beast

The procedure is now the most common surgery performed in the U.S.—more common than getting your tonsils or appendix removed.

From The Daily Beast

I shall then give an account of my various excursions in an Appendix, and afterwards resume the thread of my journal.

From Project Gutenberg

The geological character of this rock is more fully treated upon in the Appendix by my friend Dr. Fitton.

From Project Gutenberg

See Appendix I for the exact facts which were not known to me until long afterwards.

From Project Gutenberg

Mr. Brae, in the Appendix to his edition of Chaucer's Astrolabe (p. 101), has a long note on the present passage.

From Project Gutenberg

The table as prepared is set out in Appendix A to this report.

From Project Gutenberg

Related Words

• addendum
• postscript

What Is The Plural Of Appendix?

Plural word for appendix

The plural form of appendix can be either appendices, pronounced [ uh–pen-duh-seez ], or appendixes, but appendices is more widely used. The plural forms of several other singular nouns that end in -ix or -ex are also formed in this way, such as index/indices, matrix/matrices, and codex/codices.  

Irregular plurals that are formed like appendices derive directly from their original pluralization in Latin. However, the standard English plural -es is often also acceptable for these terms, as in indexes and matrixes.