radicalism

noun

ideology promoting deep changes in society and democratic reforms, typically liberal in nature, originating in the 18th and 19th centuries

Wiktionary

Pronunciation: /ˈradɪkəlɪz(ə)m/

noun

Etymology: Etymology tree English radical Proto-Indo-European *-id- Proto-Indo-European *-yéti Proto-Indo-European *-idyéti Proto-Hellenic *-íďďō Ancient Greek -ῐ́ζω (-ĭ́zō) Proto-Indo-European *-mos Proto-Indo-European *-mós Ancient Greek -μός (-mós) Ancient Greek -ισμός (-ismós)der. English -ism English radicalism From radical + -ism.

Any of various radical social or political movements that aim at fundamental change in the structure of society