hydrate
1. hy.drate \'hi--.dra-t\ n 1: a compound or complex ion formed by the union of water with some other s ubstance 2: HYDROXIDE {calcium ~} 2. hydrate \hi--'dra--sh*n\ \'hi--.dra-t-*r\ vt : to cause to take up or combine with water or the elements of water to b ecome a hydrate - hy.dra.tion n