In human beings, the opening of the stomach into the small intestine is called

In the human digestive system, the opening of the stomach into the small intestine is called the pylorus. Specifically, the pyloric orifice marks the junction between the stomach and the duodenum, which is the first segment of the small intestine [t2][t3]. This exit is regulated by a thick ring of smooth muscle known as the pyloric sphincter [t1][t6]. This sphincter acts as a valve, controlling the flow of partially digested food (chyme) from the stomach into the small intestine to ensure digestion occurs in a controlled manner [t4][t7]. In contrast, the caecum is the beginning of the large intestine, the ileum is the final section of the small intestine [t5][t8], and the oesophagus is the tube that carries food from the mouth to the stomach. The small intestine itself is the longest part of the alimentary canal, extending from the gastric pylorus to the ileocecal junction [t5][t9].

Sources

1. [1] https://en.wikipedia.org/wiki/Pylorus
2. [2] https://www.ncbi.nlm.nih.gov/books/NBK459366/