Bernoulli refers to a principle in fluid dynamics that describes the behavior of fluid flow. It states that an increase in the speed of a fluid occurs simultaneously with a decrease in pressure or potential energy. This principle is fundamental in explaining various phenomena, such as how airplanes generate lift and how carburetors work. The principle is named after Daniel Bernoulli, an 18th-century Swiss mathematician and physicist. His work laid the foundation for understanding fluid mechanics, and his findings are still widely applied in engineering, meteorology, and various scientific fields today.