diabetes insipidus: a rare form of diabetes resulting from a deficiency of vasopressin (the pituitary hormone that regulates the kidneys); characterized by the chronic excretion of large amounts of pale dilute urine which results in dehydration and extreme thirst
disease: an impairment of health or a condition of abnormal functioning
log: measuring instrument that consists of a float that trails from a ship by a knotted line in order to measure the ship's speed through the water