Final answer:
Pyloric stenosis is a condition that involves the narrowing of the pylorus, causing symptoms like vomiting, weight loss, and a palpable mass in the abdomen. The abdominal mass is usually elongated and shaped like an olive.
Step-by-step explanation:
Pyloric stenosis is a condition characterized by the narrowing of the pylorus, the opening between the stomach and the small intestine. The signs and symptoms typically include forceful vomiting, weight loss, dehydration, and a palpable mass in the abdomen. In about 85% of cases, the abdominal mass has an elongated shape, resembling an olive.