diverticulum
noun
di·ver·tic·u·lum ˌdī-vər-ˈti-kyə-ləm 
plural diverticula ˌdī-vər-ˈti-kyə-lə
1
: an abnormal pouch or sac opening from a hollow organ (such as the intestine or bladder)
2
: a pocket or closed branch opening off a main passage
diverticular
ˌdī-vər-ˈti-kyə-lər
adjective 
Example Sentences
Recent Examples on the Web As pressure increases inside the diverticulum, the cells inside get less blood flow and the wall can burst. 
Andrea K. Mcdaniels, baltimoresun.com, 7 June 2018 If the diverticulum ruptures, bacteria escape into the abdomen, leading to a more widespread infection. Andrea K. Mcdaniels, baltimoresun.com, 7 June 2018 Zenker’s diverticulum is a pouch that forms where the pharynx, or voicebox, meets the esophagus. Sandra G. Boodman, Washington Post, 17 Mar. 2018
Andrea K. Mcdaniels, baltimoresun.com, 7 June 2018 If the diverticulum ruptures, bacteria escape into the abdomen, leading to a more widespread infection. Andrea K. Mcdaniels, baltimoresun.com, 7 June 2018 Zenker’s diverticulum is a pouch that forms where the pharynx, or voicebox, meets the esophagus. Sandra G. Boodman, Washington Post, 17 Mar. 2018 Word History
Etymology
borrowed from New Latin dīverticulum, going back to Latin dēverticulum, dīverticulum "turn off the main road, byway, deviation," from dēvertere "to turn away, divert, make a turn aside/detour" + -i- -i- + -culum, suffix of instruments (going back to *-klom, -tlom) — more at divert
First Known Use
circa 1819, in the meaning defined at sense 1
Medical Definition
diverticulum
noun
di·ver·tic·u·lum ˌdī-vər-ˈtik-yə-ləm
plural diverticula -lə
1
: an abnormal pouch or sac opening from a hollow organ (as the colon or bladder)
2
: a blind tube or sac branching off from a cavity or canal of the body
the liver is an anterior diverticulum of the intestine Gordon Alexander
Gordon Alexander