'Secessionist' definitions:

Definition of 'secessionist'

(from WordNet)
noun
An advocate of secessionism

Definition of 'Secessionist'

From: GCIDE
  • Secessionist \Se*ces"sion*ist\, n.
  • 1. One who upholds secession. [1913 Webster]
  • 2. (U.S. Hist.) One who holds to the belief that a State has the right to separate from the Union at its will. [1913 Webster]