All of these names are technically correct. The water molecule has the chemical formula H2O, meaning the molecule is composed of two hydrogen atoms and one oxygen atom. Literally, the term "dihydrogen monoxide" means "two hydrogens, one oxygen": the prefix di- in dihydrogen means "two" and the prefix, mono- in monoxide means "one", and "oxide" designates oxygen in a compound. Using chemical nomenclature, other names for water include hydrogen oxide; hydrogen hydroxide, which characterizes it as a base; and several designating it as an acid, such as hydric acid, hydroxic acid, hydroxyl acid, hydrohydroxic acid, and hydroxilic acid. The term used in the original text, hydroxyl acid, is a non-standard name.

Source: Wikipedia