'Rioter' definitions:

Definition of 'rioter'

From: WordNet
noun
Troublemaker who participates in a violent disturbance of the peace; someone who rises up against the constituted authority

Definition of 'Rioter'

From: GCIDE
  • Rioter \Ri"ot*er\, n.
  • 1. One who riots; a reveler; a roisterer. --Chaucer. [1913 Webster]
  • 2. (Law) One who engages in a riot. See Riot, n., 3. [1913 Webster]