3. (Aeronautics) any structure corresponding to or resembling the keel of a ship, such as the central member along the bottom of an aircraft fuselage. 4. (Biology) biology a ridgelike part; carina. 5. a poetic word for ship.
Transverse colon and sigmoid colon. The transverse colon and the sigmoid colon have a mesentery (ie, transverse mesocolon and sigmoid mesocolon, respectively), but the ascending colon and descending colon are retroperitoneal, while the cecum is intraperitoneal but uses the mesentery of the ileum.
The sigmoid colon refers to the lower portion of the colon. In  people who have diverticulitis, the sigmoid colon walls will  develop pouches which trap food. This causes inâ¦testinal pain and  bowel problems.