Hygroscope :: Hygroscope (n.) An instrument which shows whether there is more or less moisture in the atmosphere, without indicating its amount..
Hygroscopic :: Hygroscopic (a.) Of or pertaining to, or indicated by, the hygroscope; not readily manifest to the senses, but capable of detection by the hygroscope; as, glass is often covered with a film of hygroscopic moisture..
Hygroscopic :: Hygroscopic (a.) Having the property of readily inbibing moisture from the atmosphere, or of the becoming coated with a thin film of moisture, as glass, etc..
Hygroscopicity :: Hygroscopicity (n.) The property possessed by vegetable tissues of absorbing or discharging moisture according to circumstances.