H2O is the chemical formula for water, commonly used to refer to water in scientific, educational, and casual contexts. In pronunciation, it is spoken as the sequence of letters and numbers in abbreviation form, typically rendered as a three-part token rather than a full word, e.g., 'aitch-two-oh' or simply 'H-2-O' depending on the context. It functions as a noun describing a ubiquitous liquid substance essential to life.
Full pronunciation guide
