%mesenteron%

‖n. [ NL. See Meso-, and Enteron. ] (Anat.) All that part of the alimentary canal which is developed from the primitive enteron and is lined with hypoblast. It is distinguished from the stomodaeum, a part at the anterior end of the canal, including the cavity of the mouth, and the proctodaeum, a part at the posterior end, which are formed by invagination and are lined with epiblast. [ 1913 Webster ]