Radical

(chemistry) two or more atoms bound together as a single unit and forming part of a molecule

an atom or group of atoms with at least one unpaired electron

a person who has radical ideas or opinions

(mathematics) a quantity expressed as the root of another quantity

a character conveying the lexical meaning of a logogram

(linguistics) the form of a word after all affixes are removed

(used of opinions and actions) far beyond the norm

markedly new or introducing radical change

arising from or going to the root or source

of or relating to or constituting a linguistic root

especially of leaves