Definition

Noun: * The pyloric sphincter muscle: A ring of smooth muscle that surrounds and controls the opening (the pylorus) between the stomach and the duodenum (the first part of the small intestine). Its primary function is to regulate the passage of partially digested food (chyme) from the stomach into the small intestine.

Usage

• The term is used in formal, academic, and medical contexts to describe this specific anatomical structure.
• It is often discussed in relation to digestion, gastrointestinal physiology, and medical conditions affecting gastric emptying.

Examples

• Noun:
  • The musculus sphincter pylori relaxes periodically to allow chyme to enter the duodenum.
  • A dysfunction of the musculus sphincter pylori can lead to conditions like gastroparesis or pyloric stenosis.

Advanced Usage

• Physiological Role: The musculus sphincter pylori remains tonically contracted to prevent the backflow (reflux) of duodenal contents into the stomach and to allow the stomach adequate time to mechanically and chemically process food.
• Clinical Relevance: It is a key structure studied in gastroenterology. Its failure to relax properly can cause delayed gastric emptying, while hypertrophy (excessive growth) in infants is known as hypertrophic pyloric stenosis.

Variants and Related Words

• Pyloric sphincter (n): The most common synonymous term in both medical and lay contexts.
• Pylorus (n): The opening or canal itself, which is surrounded by the musculus sphincter pylori.
• Sphincter muscle (n): The general type of muscle, which is circular and acts as a valve.

Synonyms

• Pyloric sphincter
• Pyloric valve (less precise, but commonly used)

Related Phrases / Terms

• Gastric emptying: The process controlled by this sphincter.
• Chyme: The semi-fluid mass of partly digested food that passes through this sphincter.
• Duodenum: The anatomical structure immediately following this sphincter.

Noun

1. the sphincter muscle of the pylorus that separates the stomach from the duodenum