appendix

[uh-pen-diks]

noun

plural

appendices, appendixes 

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

   Synonyms: supplement, addition, appurtenance, adjunct, addendum

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. anatomy See vermiform appendix

appendix

plural

appendixes 

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

Irwin wrote that after "13 years of fighting for answers" and two surgeries where she had 51 lesions, a cyst and her appendix removed, she was finally on the mend.

From BBC

Durham made no determination in his appendix whether the emails were authentic, or if they had been doctored by Russian spies.

From BBC

For different levels of difficult behaviour the appendix to the guidelines suggests different staged interventions.

From BBC

It is thought to be made of a sheep's appendix and features an explicit print representing a nun and three clergymen.

From BBC

Ms Bulloch's endometriosis eventually affected her bowel, appendix and left ovary.

From BBC

Related Words

• addendum 
• postscript 

When To Use

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.