- a person who favors or takes part in secession, or upholds the right to secede
- [oftenS-] one who favored the secession of the Southern states
A common usage is for supporters of the Confederacy during the United States Civil War.
(comparative more secessionist, superlative most secessionist)
As well as being applied to people and movements, 'secessionist' is commonly used to describe opinions or beliefs and the form of their expression in books, articles, or speeches.