Word Study
bistort
CIDE DICTIONARY
bistort, n. [L. bis + tortus, p. p. of torquere to twist: cf. F. bistorte.].
An herbaceous plant of the genus Polygonum , section Bistorta ; snakeweed; adderwort. Its root is used in medicine as an astringent. [1913 Webster]
OXFORD DICTIONARY
bistort, n. a herb, Polygonum bistorta, with a twisted root and a cylindrical spike of flesh-coloured flowers.
Etymology
F bistorte or med.L bistorta f. bis twice + torta fem. past part. of torquere twist
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