Relating or pertaining to Richard Cameron (see II.) or to the Cameronians: as, a Cameronian clergyman.n. One of the followers of Richard Cameron in Scotland, who refused to accept the indulgence granted to the Presbyterian clergy in the persecuting times of Charles II., lest by so doing they should be understood to recognize his ecclesiastical authority.n. plural A name given to the 26th regiment of British infantry, from its having been originally composed of the Cameronians who flocked to Edinburgh during the revolution of 1688.