DictionaryradicalFundamental change
adjective / noun

radical

RAD-ih-kuhl/ˈrædɪkl/

Departing substantially from established practices.

The advocate proposes a radical change: replacing royal rule with voting.

A forceful advocate proposes replacing royal rule with voting: he pushes away a large model of a crowned throne elevated above ordinary citizens and presents a replacement model centered on a ballot box accessible to those same citizens.
Etymology

Something radical concerns the “root,” hence the origin or essentials of a thing. Applied to reform, this became change “from the roots”: altering a system fundamentally rather than adjusting its surface.

In context

Wikipedia Fan90:53
calling for radical social and political change
Nazi | Wikipedia audio article

More examples

  • Working from home requires a radical shift in our routines.
  • The radicals demand an entirely new system of government.
  • That skateboard trick is radical!

Forms

radical · radicals · more radical · most radical

radically adverb — In a way that changes basic features.

radicalism noun — Support for fundamental political or social change.

Similar words

revolutionary
Suggests overturning an existing system, not merely changing its practices.
sweeping
Emphasizes how widely changes apply rather than their fundamental nature.
unconventional
Departs from usual practices without necessarily seeking fundamental change.