In the embryo, the mesentery of the dilated portion of the foregut that is the future stomach; it gives rise to the greater omentum and consequently is involved in the formation of the omental bursa. The spleen and body of the pancreas develop within it, and thus the splenorenal and gastrosplenic ligaments are derivatives of the (dorsal) mesogastrium.
[meso- + G. gaster stomach]
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Examples: glitazone, GI cocktail, etc.