Hyperthyroidism – too much thyroid hormones only from the thyroid gland
Thyrotoxicosis – too much thyroid hormone from any cause (i.e. taking too much thyroid supplement)
Thyroid Storm – see above. Thyrotoxicosis with increased adrenergic hyperactivity or abnormal response to the thyroid hormones by the peripheral tissues
Myxedema coma – These patients are the opposite of thyroid storm, all the systems are depressed (they are essentially hypo-everything).