graves' disease: exophthalmos occurring in association with goiter; hyperthyroidism with protrusion of the eyeballs
hyperthyroidism: an overactive thyroid gland; pathologically excessive production of thyroid hormones or the condition resulting from excessive production of thyroid hormones
differential calculus: the part of calculus that deals with the variation of a function with respect to changes in the independent variable (or variables) by means of the concepts of derivative and differential