Dercum disease: A condition characterized by painful fatty tumors (lipomas) beneath the skin. The diseases tends to be associated with obesity and is about 5 times more frequent in females than in males. Onset of symptoms is generally in middle age. The fatty tumors are most often located on the trunk and limbs with sparing of the face and hands Also called adiposis dolorosa. Named for the Philadelphia neurologist Francis X. Dercum (1856-1931).