butternut

plural butternuts

1. countableuncountableA North American walnut tree, Juglans cinerea.

   Synonyms: white walnut

2. countableuncountableThe wood or bark of this walnut tree.
3. countableuncountableThe nut of this walnut tree.
4. countableuncountableA dye made from the fruit of this walnut tree.
5. countableuncountableThe souari nut.
6. countableuncountableinformal outside South AfricaButternut squash.

   He made a delicious butternut soup.

plural Butternuts

1. USobsoleteSouthern settlers of the Ohio river basin, who used dye from the butternut tree to colour their home-made clothing

   Yankees took to calling the Borderlanders “butternuts”—a reference to the color of their crude homespun clothes.

   2011, Colin Woodard, chapter 17, in American nations, New York: Penguin, →ISBN

2. USobsoleteA Confederate Southerner, or somebody who supported southern rights and slaveryFirst known use 19th c.

   The Illinois troops delivered a volley that sent the butternuts scampering back across the field.

   1958, Shelby Foote, The Civil War: A Narrative. Vol. 1: Fort Sumter to Perryville.