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Adjective: radical  ra-di-kul
  1. (used of opinions and actions) far beyond the norm
    "radical opinions on education";
    - extremist, ultra
     
  2. Markedly new or introducing fundamental change
    "radical political views";
    - revolutionary
     
  3. Arising from or going to the root or source
    "a radical flaw in the plan"
     
  4. (linguistics) of or relating to or constituting a linguistic root
    "a radical verb form"
     
  5. (botany) 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
    "radical leaves";
    - basal
     
  6. [N. Amer, slang] Brilliant; very good
    - socko [N. Amer, informal], righteous [US, slang], fab [Brit, informal], crucial [slang], rad [N. Amer, slang], nang [Brit, slang], phat [slang], legit [US, slang], awesomesauce [informal], amazeballs [informal], beaut [Austral, NZ, informal], lit [US, slang], storming [Brit, informal], blinding [Brit, slang], stonking [Brit, informal], brill [Brit, informal], wicked [slang], cushty [Brit, informal], ace [informal], def [slang], magic [Brit, slang], smokin' [slang], smoking [slang], super [informal], sick [N. Amer, slang]
Noun: radical  ra-di-kul
  1. A person who has radical ideas or opinions
    - rad [informal]
     
  2. (chemistry) two or more atoms bound together as a single unit and forming part of a molecule
    - group, chemical group
     
  3. 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";
    - free radical
     
  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 radical";
    - root, root word, base, stem, theme

Sounds like: racks, wadical, r

Derived forms: radicals

See also: A1 [informal], ace [informal], A-one [informal], awesome [informal], basic, beezer [UK, archaic], brilliant, crack [informal], excellent, fantabulous [informal], first-class, first-rate, immoderate, lush [Brit, informal], new, outstanding, ripping [Brit, informal], splendid, stellar [informal], super, tiptop, top-drawer, topnotch [informal], top-notch [informal], tops [informal]

Type of: amount, atom, building block, character, descriptor, form, graph, grapheme, graphic symbol, individual, measure, mortal, person, quantity, signifier, somebody, someone, soul, unit, word form

Antonym: cauline

Part of: ideogram, ideograph, molecule

Encyclopedia: Radical, Republican, Democratic and Progressive