👉 The Thomas Fluid, also known as Thomas' Fluid or Thomas' Hypogastric Vein, is a theoretical anatomical structure proposed by the American anatomist Thomas Willis in the 17th century. According to this concept, there is a network of small veins and vessels located in the lower abdomen, specifically within the hypogastric region, that are thought to drain blood from various abdominal organs. However, modern medical science has largely dismissed the existence of a distinct Thomas Fluid as it lacks robust clinical evidence and is not recognized in contemporary anatomical textbooks. The name itself was coined by Willis, reflecting his interest in understanding the circulatory system and its lesser-known components.