hygrometer Syllabification: (hy·grom·e·ter)Pronunciation: /hīˈgrämitər/Definition of hygrometer noun an instrument for measuring the humidity of the air or a gas. Derivatives hygrometricPronunciation: /ˌhīgrəˈmetrik/ adjective hygrometryPronunciation: /-trē/ noun hygrometer in other Oxford dictionaries Definition of hygrometer in the British & World English dictionary