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horse chestnut

noun
  1. a tree, Aesculus hippocastanum, native to the Old World, having digitate leaves and upright clusters of white flowers.
  2. the shiny, brown, nutlike seed of this tree or of other trees of the genus Aesculus.

Origin of horse chestnut

1590–1600; translation of New Latin castanea equīna; so named from its use in treating respiratory diseases of horses
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for horse chestnut

horse chestnut

noun
  1. any of several trees of the genus Aesculus, esp the Eurasian A. hippocastanum, having palmate leaves, erect clusters of white, pink, or red flowers, and brown shiny inedible nuts enclosed in a spiky bur: family Hippocastanaceae
  2. Also called: conker the nut of this tree

Word Origin for horse chestnut

C16: so called from its having been used in the treatment of respiratory disease in horses
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