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chaste tree

noun
  1. a shrub or small tree, Vitex agnus-castus, of southern Europe, having aromatic, hairy leaves and long clusters of fragrant, pale lilac-blue flowers.

Origin of chaste tree

1555–65; translation of Latin agnus castus, variant of agnos castus (by influence of agnus lamb) < Greek ágnos kind of willow + Latin castus chaste, reinforcement of the idea thought to be in ágnos by confusion with Greek hagnós pure
Also called hemp tree, monk's pepper tree.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for chaste tree

chaste tree

noun
  1. a small ornamental verbenaceous tree, Vitex agnus-castus, of S Europe and SW Asia, with spikes of pale blue flowers
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012