n 1  cap  :  a genus of poisonous Eurasian herbs of the family Solanaceae that have simple leaves, somewhat irregular flowers, and circumscissile capsular fruit and include the henbane (H. niger)  2  :  the dried leaves of the henbane containing the alkaloids hyoscyamine and scopolamine and used as an antispasmodic and sedative .
 
 
 
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