Source : Webster's Revised Unabridged Dictionary (1913)

Hyoscine \Hy*os"cine\, n. [See {Hyoscyamus}.] (Chem.)
   An alkaloid found with hyoscyamine (with which it is also
   isomeric) in henbane, and extracted as a white, amorphous,
   semisolid substance.

Source : WordNet®

hyoscine
     n : an alkaloid with anticholinergic effects that is used as a
         sedative and to treat nausea and to dilate the pupils in
         ophthalmic procedures; "transdermal scopolamine is used
         to treat motion sickness"; "someone sedated with
         scopolamine has difficulty lying" [syn: {scopolamine}]