Cholelithiasis is the medical term for the formation of gallstones in the gallbladder. These solid particles can vary in size and composition, often consisting of cholesterol or bilirubin. Cholelithiasis can lead to symptoms such as abdominal pain, nausea, and digestive issues, and may require treatment if complications arise. Management options include dietary changes, medication, or surgical removal of the gallbladder (cholecystectomy).