appendix

in anatomy
https://doi.org/10.1351/goldbook.10422
  1. Tube-shaped sac ("vermiform appendix") attached to and opening into the upper end of the large intestine (cecum) in humans and some other mammals.
  2. Appendage, blind sac, or diverticulum.
Source:
PAC, 2016, 88, 713. (Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)) on page 726 [Terms] [Paper]