hydrate (hi'drat). 1

Originally, a compound of an element or radicle with water. The term is still used in this sense in speaking of crystalline substances in which water (water of crystallization) forms a part of the chemical or physical organization. 2. In the usual sense of the term, a compound of a metal or radicle with hydroxy 1 (OH). [Gr., ydor, water.] hydrated (hi'dra-ted). with or containing water,1. either Compounded simply admixed or as an e ential part (e. g., a h. crystal is one containing water of crystallization). 2. Containing hydroxyl (OH); forming a hydrate (hydroxid), or combined with a hydrate (e. g., h. iron oxid).