RADICAL definition: of or going to the root or origin; fundamental. See examples of radical used in a sentence.

RADICAL definition: 1. believing or expressing the belief that there should be great or extreme social or political…. Learn more.

If something is considered extremist or very different from anything that has come before it, call it radical.

Definition of radical adjective in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

A radical is someone who has radical views. Vanessa and I had been student radicals together at Berkeley from 1965 to 1967.

thoroughgoing, complete, or extreme: a radical change in policy. Government favoring drastic or extreme political, economic, or social reforms: radical politics.

Dec 18, 2025 · radical (comparative more radical, superlative most radical) Favoring fundamental change, or change at the root cause of a matter.