Appendix Health Dictionary

A small, narrow tube that projects out of the caecum (the 1st part of the colon) at the lower right-hand side of the abdomen. It may lie behind or below the caecum, or in front of or behind the ileum (part of the small intestine). The appendix has no known function, but it contains a large amount of lymphoid tissue which provides a

defence against local infection. The position of an individual’s appendix partly determines the set of symptoms produced by acute appendicitis (inflammation of the appendix).

A term applied to the appendages of several hollow organs: for example, the larynx has two pouches called appendices, and the epiploic appendices are the tags of fat that hang from the exterior part of the large intestine. The commonest application, however, is to the vermiform appendix of the large intestine. This is a short, slim, blind-ended tube up to 10 cm long attached to the caecum (a pouch at the start of the large intestine). Its function is unknown, though it may once have had one in ancestral humans. It is, however, prone to in?ammation and infection (see APPENDICITIS).

(vermiform appendix) n. the short thin blind-ended tube, 7–10 cm long, that is attached to the end of the caecum (a pouch at the start of the large intestine). It has no known function in humans and is liable to become infected and inflamed, especially in young adults (see appendicitis).