A thoroughgoing reform; specifically a reform of the British social and parliamentary system called for during the end of the 18th and early 19th cent. by those opposed to George III's parliamentary control.
Origin
Late 18th century.
Definition of radical reform in US English:
radical reform
noun
A thoroughgoing reform; specifically a reform of the British social and parliamentary system called for during the end of the 18th and early 19th cent. by those opposed to George III's parliamentary control.