Definition of "valerian"

valerian

/vəˈlɪəɹɪən/

noun
countable and uncountable, plural valerians
1. A hardy perennial flowering plant, Valeriana officinalis, with heads of sweetly scented pink or white flowers.
  Quotations
  In the event of anyone wishing to invoke the very Prince of Spirits, the following ingredients were prescribed to be burnt - Juice of Hypericon, Saffron, Artemisia, and the root of Valerian.
  1936, Rollo Ahmed, The Black Art, London: Long, page 112
2. More generally, any plant of the genus Valeriana.
3. (uncountable) The root of Valeriana officinalis, used in herbal medicine.
4. An extract of the dried roots of the Valeriana officinalis used in herbal medicine as a sedative.