Pneumogastric adj. (Anat.) Of or pertaining to the lungs and the stomach. Pneumogastric nerve (Anat.), one of the tenth pair of cranial nerves which are distributed to the pharynx, esophagus, larynx, lungs, heart, stomach, liver, and spleen, and, in fishes and many amphibia, to the branchial apparatus and also to the sides of the body.