valerian vs water parsnip

valerian

noun
  • More generally, any plant of the genus Valeriana. 

  • An extract of the dried roots of the Valeriana officinalis used in herbal medicine as a sedative. 

  • A hardy perennial flowering plant, Valeriana officinalis, with heads of sweetly scented pink or white flowers. 

  • The root of Valeriana officinalis, used in herbal medicine. 

water parsnip

noun
  • Any plant of the genus Sium, as the skirret. 

How often have the words valerian and water parsnip occurred in a corpus of books? (source: Google Ngram Viewer )