The Collaborative International Dictionary of English v.0.48:
Mesogastric \Mes`o*gas"tric\, a. [Meso- + gastric.] [1913 Webster] 1. (Anat.) (a) Of or pertaining to the middle region of the abdomen, or of the stomach. (b) Of or pertaining to the mesogaster. [1913 Webster] 2. (Zool.) Of or pertaining to the middle gastric lobe of the carapace of a crab. [1913 Webster]