endocrine, hormone, internal secretion - the secretion of an endocrine gland that is transmitted by the blood to the tissue on which it has a specific effect

calcitonin, thyrocalcitonin - thyroid hormone that tends to lower the level of calcium in the blood plasma and inhibit resorption of bone

tetraiodothyronine, thyroxin, thyroxine, T - hormone produced by the thyroid glands to regulate metabolism by controlling the rate of oxidation in cells; "thyroxine is 65% iodine"

liothyronine, triiodothyronine, T - thyroid hormone similar to thyroxine but with one less iodine atom per molecule and produced in smaller quantity; exerts the same biological effects as thyroxine but is more potent and briefer