What is Chestnut ?
Chestnut is (noun) 1. horse chestnut, sweet chestnut (trees) 2. a large reddish-brown shiny nut, from a horse chestnut or sweet chestnut tree 3. the wood from a chestnut tree a chestnut table 4. a red-brown colour She has beautiful long chestnut hair. 5. a red-brown horse Do you know the name of the chestnut that came last? 6. an old joke His speech was just a series of not very amusing old chestnuts.
source: Easier English, Student Dictionary Upper Intermediate Level