'Radicalism' definitions:

Definition of 'radicalism'

From: WordNet
noun
The political orientation of those who favor revolutionary change in government and society

Definition of 'Radicalism'

From: GCIDE
  • Radicalism \Rad"i*cal*ism\ (r[a^]d"[i^]*kal*[i^]z'm), n. [Cf. F. radicalisme.] The quality or state of being radical; specifically, the doctrines or principles of radicals in politics or social reform. [1913 Webster]
  • Radicalism means root work; the uprooting of all falsehoods and abuses. --F. W. Robertson. [1913 Webster]