What is the meaning of chestnut?

noun

• Wood of any of various chestnut trees of the genus Castanea.
• Any of several attractive deciduous trees yellow-brown in autumn; yield a hard wood and edible nuts in a prickly bur.
  • synonyms: chestnut tree
• Edible nut of any of various chestnut trees of the genus Castanea.
• The brown color of chestnuts.
• A small horny callus on the inner surface of a horse's leg.
• A dark golden-brown or reddish-brown horse.

adjective

• Of hair or feathers. ( of a golden brown to reddish brown color)
  • usage: "a chestnut horse"; "chestnut hair"