1.  appendix(n = noun.communication) - supplementary material that is collected and appended at the back of a book;
is a kind of addendum, postscript, supplement
has particulars: shirttail, codicil

2.  appendix(n = noun.body) cecal appendage, vermiform appendix, vermiform process - a vestigial process that extends from the lower end of the cecum and that resembles a small pouch;
is a kind of appendage, outgrowth, process
is a part of blind gut, caecum, cecum

1.  Something appended or added; an appendage, adjunct, or concomitant. [1913 Webster]
"Normandy became an appendix to England." [1913 Webster]

2.  Any literary matter added to a book, but not necessarily essential to its completeness, and thus distinguished from supplement, which is intended to supply deficiencies and correct inaccuracies. [1913 Webster]

3.  The vermiform appendix. [Webster 1913 Suppl.]

appendix, n. (pl. appendices; appendixes)
1 (in full vermiform appendix) Anat. a small outgrowth of tissue forming a tube-shaped sac attached to the lower end of the large intestine.
2 subsidiary matter at the end of a book or document.

Etymology:
L appendix -icis f. appendere APPEND

N  sequel, suffix, successor, tail, queue, train, wake, trail, rear, retinue, suite, appendix, postscript, epilogue, peroration, codicil, continuation, sequela, appendage, tail piece, heelpiece, tag, more last words, colophon, aftercome, aftergrowth, afterpart, afterpiece, aftercourse, afterthought, aftergame, arriere pensee, second thoughts, outgrowth.

appendix vermiformis, auricular appendix, vermiform appendix