Webster's Revised Unabridged Dictionary · 1913

Radicalism

Radicalism (rad"i*kal*iz'm) , noun

[Compare French radicalisme.]

The quality or state of being radical; specifically, the doctrines or principles of radicals in politics or social reform.
Radicalism means root work; the uprooting of all falsehoods and abuses. — F. W. Robertson