noun
- Zoology.
- the middle portion of the vertebrate alimentary canal, posterior to the stomach or gizzard and extending to the cecum, functioning in the digestion and absorption of food; the small intestine.
- the anterior portion of the arthropod colon, composed of endodermal tissue.
- Embryology. the middle part of the embryonic alimentary canal from which the intestines develop.
noun
- the middle part of the digestive tract of vertebrates, including the small intestine
- the middle part of the digestive tract of arthropods
n.
- The middle section of the digestive tract in a vertebrate embryo from which the ileum, jejunum, and portions of the duodenum and colon develop.mesenteron
- The middle portion of the digestive tract of certain invertebrates, such as arthropods, that is lined with an enzyme-secreting tissue and that serves as the main site of digestion and absorption.