Stenosis pylori - thickening of the muscle between the stomach and the intestines

Pyloric stenosis is a condition in which the muscle at the outlet of the stomach (pylorus) becomes abnormally thickened, leading to a narrowing or blockage. 

This can result in symptoms such as projectile vomiting, poor weight gain, and dehydration, typically occurring in infants within the first few weeks or months of life. 

Prompt medical evaluation and surgical intervention are often necessary to treat pyloric stenosis.