Meaning & Definition of Radical in English

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

2. An atom or group of atoms with at least one unpaired electron

• In the body it is usually an oxygen molecule that has lost an electron and will stabilize itself by stealing an electron from a nearby molecule

• "In the body free radicals are high-energy particles that ricochet wildly and damage cells"

3. A person who has radical ideas or opinions

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

5. A character conveying the lexical meaning of a logogram

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

• "Thematic vowels are part of the stem"

1. (used of opinions and actions) far beyond the norm

• "Extremist political views"

• "Radical opinions on education"

• "An ultra conservative"

2. Markedly new or introducing radical change

• "A revolutionary discovery"

• "Radical political views"

3. Arising from or going to the root or source

• "A radical flaw in the plan"

4. Of or relating to or constituting a linguistic root

• "A radical verb form"

5. Especially of leaves

• Located at the base of a plant or stem

• Especially arising directly from the root or rootstock or a root-like stem

• "Basal placentation"

• "Radical leaves"