Aeronautics. the short tube at the bottom of a balloon bag, by which the intake and release of buoyant gas is controlled.
Origin of appendix
1535–45; < Latin: appendage, equivalent to append(ere) to append + -ix (equivalent to -ic- noun suffix + -s nominative singular ending)
Can be confusedappendixindexsupplement (see synonym study at the current entry)
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.
Appendices, a plural borrowed directly from Latin, is sometimes used, especially in scholarly writing, to refer to supplementary material at the end of a book.
1540s, "subjoined addition to a document or book," from Latin appendix "an addition, continuation, something attached," from appendere (see append). Used for "small outgrowth of an internal organ" from 1610s, especially in reference to the vermiform appendix. This sense perhaps from or influenced by French appendix, where the term was in use from 1540s.
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.