Hygroscopic \Hy`gro*scop"ic\, a. [Cf. F. hygroscopique.]
1. 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.
[1913 Webster]
2. Having the property of readily inbibing moisture from the
atmosphere, or of the becoming coated with a thin film of
moisture, as glass, etc.
[1913 Webster]