Noun
a hydrate that contains one molecule of water per molecule of the compound
Source: WordNetThe salts of methadone in use are the hydrobromide (free base conversion ratio 0.793), hydrochloride (0.894), and HCl monohydrate (0.850). Source: Internet
The anhydrous form crystallizes from hot water, while the monohydrate forms when citric acid is crystallized from cold water. Source: Internet