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.
A sigmoidoscopy is a diagnostic test to check the lower part of your colon or large intestine (the sigmoid colon). This part of your colon is close to your rectum and anus. A sigmoidoscopy may also be used to take a tissue sample or biopsy.