The meaning of RADICAL is of, relating to, or proceeding from a root. How to use radical in a sentence.

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.

a person holding radical views, esp. one favoring fundamental social or economic change

Relating to or advocating fundamental or revolutionary changes in current practices, conditions, or institutions: radical politics; a radical political theorist.

The indicated root of a quantity or quantities, shown by an expression written under the radical sign.

4 days ago · Favoring fundamental change, or change at the root cause of a matter. His beliefs are radical. The spread of the cancer required radical surgery, and the entire organ was removed. …

thoroughgoing or extreme, esp. as regards change from accepted or traditional forms:a radical change in the policy of a company. Governmentfavoring drastic political, economic, or social reforms:radical …

In chemistry, a radical is an atom, molecule, or ion that has unpaired valence electrons or an open electron shell, and therefore may be seen as having one or more "dangling" covalent bonds.

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