Pag·et \ˈpaj-ət\ , Sir James (1814–1899), British surgeon. Along with the German biologist Rudolf Virchow, Paget is considered one of the founders of the science of pathology. In 1834 he discovered in human muscle the parasitic worm that causes trichinosis. A professor of anatomy and surgery, he wrote classic descriptions of breast cancer, of a chronic precancerous eczema of the nipple (1874), and of osteitis deformans (1877). Both of these last two conditions are often called Paget's disease.