A single sac is called a diverticulum. Two or more sacs are called diverticula.
By far, the most common site for diverticula to develop is in the large intestine Large Intestine The large intestine consists of the Cecum and ascending (right) colon Transverse colon Descending (left) colon Sigmoid colon (which is connected to the rectum) read more (colon). Diverticula of the colon occur when the inner layers of the bowel protrude through the outer muscular layers.
Diverticula may also develop in the esophagus Esophageal Pouches (Diverticula) Esophageal diverticula are abnormal pouches or pockets in the esophagus. Rarely, they cause swallowing difficulties and regurgitation (the spitting up of food without nausea or forceful contractions... read more 
and rarely in the stomach. Meckel diverticulum Meckel Diverticulum A Meckel diverticulum is a saclike outpouching of the wall of the small intestine that is present in some children at birth. Most children do not have symptoms, but sometimes painless rectal... read more is a common diverticular disease of the small intestine. It is present at birth in about 2 to 3% of people.
The Digestive System
 |
The presence of one or more diverticula in the colon is called diverticulosis Diverticulosis of the Large Intestine Diverticulosis is the presence of one or more balloon-like sacs (diverticula), usually in the large intestine (colon). The cause of diverticulosis is unknown but may be related to diet, a sedentary... read more 
. Diverticulosis is a condition that tends to develop during middle age.
If diverticula become inflamed, the condition is called diverticulitis Diverticulitis Diverticulitis is inflammation of one or more balloon-like sacs (diverticula). Infection may or may not develop. Diverticulitis usually affects the large intestine (colon). Left lower abdominal... read more 
. Diverticulitis can develop with or without infection of a diverticulum.
