Visceri

Visceri is a term used to refer collectively to the internal organs of the body, typically those within the thoracic, abdominal, and pelvic cavities. In English, the standard plural form is viscera; visceri appears mainly in non-English contexts or as a historical variant. The viscera encompass a wide range of organs with diverse functions, including circulation, digestion, respiration, and reproduction.

The viscera are commonly categorized by body cavity. Thoracic viscera include the heart and lungs, along with other mediastinal structures. Abdominal viscera comprise the stomach, intestines, liver, gallbladder, pancreas, spleen, and kidneys, among others, often described together with those in the retroperitoneal space. Pelvic viscera include the urinary bladder and portions of the reproductive system (in females and males), as well as segments of the distal digestive tract such as the rectum.

Anatomically, many viscera are covered by serous membranes; the surfaces are lined by visceral peritoneum where the organ contacts the cavity and by parietal peritoneum lining the cavity walls. Visceral sensation, particularly pain, is typically conveyed by autonomic nerves and is often poorly localized compared with somatic pain. The concept of viscera also underpins fields such as visceral anatomy and splanchnology.

Clinical relevance includes the assessment of organ health, disease processes affecting internal organs, and surgical approaches that consider the relationships and coverings of the viscera. Etymologically, the term derives from Latin viscera, the plural of viscus, with visceri representing a plural form used in some languages.