Definition of red horse chestnut in English:

red horse chestnut

noun

  • 1A cultivated tree, Aesculus× carnea, a fertile hybrid between the horse chestnut, A. hippocastanum, and the red buckeye, A. pavia.

  • 2(Probably) the red buckeye, A. pavia (rare).

Origin

Mid 18th century; earliest use found in Philosophical Transactions of the Royal Society of London.