Ventral mesentery is the part of the peritoneum closest to the navel.
Ventral mesentery Wikipedia
The development of the septum transversum takes part in the formation of the diaphragm, while the caudal portion into which the liver grows forms the ventral mesentery. The part of the ventral mesentery that attaches to the stomach is known as the ventral mesogastrium.
The lesser omentum is formed, by a thinning of the mesoderm or ventral mesogastrium, which attaches the stomach and duodenum to the anterior abdominal wall. By the subsequent growth of the liver this leaf of mesoderm is divided into two parts, viz., the lesser omentum between the stomach and liver, and the falciform and coronary ligaments between the liver and the abdominal wall and diaphragm.