1854, from de- + hydrate (v.). A chemical term at first, given a broader extension 1880s. Related: Dehydration (1834).[dehydrate etymology, dehydrate origin, 英语词源]
"A disease in which the secretion of or response to the pituitary hormone vasopressin is impaired, resulting in the production of very large quantities of dilute urine, often with dehydration and insatiable thirst", Late 19th century: from diabetes + Latininsipidus 'insipid'.