What does radical change mean?

Radical Change is a conservative liberal political party in Colombia. At the last legislative elections in Colombia on March 12, 2006, the party became one of the most important in the new Congress, receiving 15 seats in the lower house and 20 in the upper house. Along with the Social National Unity Party, or "de la U" party and the Conservative Party, it was president Álvaro Uribe's main ally in Congress and formed part of his absolute majority.

thoroughgoing or extreme, especially as regards change from accepted or traditional forms: a radical change in the policy of a company. 3. favoring drastic political, economic, or social reforms: radical ideas; radical and anarchistic ideologues.