radical

¹rad·i·cal

adj \ˈra-di-kəl\

Definition of RADICAL

1

: of, relating to, or proceeding from a root: as a (1) : of or growing from the root of a plant <radical tubers> (2) : growing from the base of a stem, from a rootlike stem, or from a stem that does not rise above the ground <radical leaves> b : of, relating to, or constituting a linguistic root c : of or relating to a mathematical root d : designed to remove the root of a disease or all diseased and potentially diseased tissue <radical surgery> <radical mastectomy>

2

: of or relating to the origin : fundamental

3

a : marked by a considerable departure from the usual or traditional : extreme b : tending or disposed to make extreme changes in existing views, habits, conditions, or institutions c : of, relating to, or constituting a political group associated with views, practices, and policies of extreme change d : advocating extreme measures to retain or restore a political state of affairs <the radical right>

4

slang : excellent, cool

— rad·i·cal·ness noun

Examples of RADICAL

1. The computer has introduced radical innovations.
2. There are some radical differences between the two proposals.
3. The new president has made some radical changes to the company.
4. a radical wing of extremists

Origin of RADICAL

Middle English, from Late Latin radicalis, from Latin radic-, radix root — more at root

First Known Use: 14th century

Related to RADICAL

Synonyms: extremist, fanatic (or fanatical), rabid, extreme, revolutionary, revolutionist, ultra

Antonyms: middle-of-the-road, nonrevolutionary, unrevolutionary

Related Words: subversive, violent, wild; reactionary

Near Antonyms: conservative, moderate, temperate; conventional, orthodox, traditional; liberal, progressive

see all synonyms and antonyms

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