hydrate (n.) Look up hydrate at Dictionary.com
1802, "compound of water and another chemical," from French hydrate, coined c.1800 by French chemist Joseph-Louis Proust (1754-1826) from Greek hydr-, stem of hydor "water" (see water (n.1)).
hydrate (v.) Look up hydrate at Dictionary.com
1850, "to form a hydrate;" 1947 as "to restore moisture;" from Greek hydr-, stem of hydor "water" (see water (n.1)) + -ate (2). Related: Hydrated; hydrating.