Copperheadism

English

Etymology

From Copperhead +‎ -ism.

Noun

Copperheadism (uncountable)

1. (US, historical) The state of being a Copperhead; sympathy in the North for Southern secessionists during the American Civil War.
   • 1988, James McPherson, Battle Cry of Freedom, Oxford, published 2003, page 247:

     The project went nowhere, but it did plant seeds of copperheadism that germinated a couple of years later.