Definitions of radical:

  • noun:   a sign placed in front of an expression to denote that a root is to be extracted
  • noun:   a character conveying the lexical meaning of a logogram
  • noun:   a person who has radical ideas or opinions
  • noun:   (chemistry) two or more atoms bound together as a single unit and forming part of a molecule
  • noun:   an atom or group of atoms with at least one unpaired electron; in the body it is usually an oxygen molecule than has lost an electron and will stabilize itself by stealing an electron from a nearby molecule
    Example: "In the body free radicals are high-energy particles that ricochet wildly and damage cells"
  • noun:   (linguistics) the form of a word after all affixes are removed
  • adjective:   arising from or going to the root
    Example: "A radical flaw in the plan"
  • adjective:   of or relating to or constituting a linguistic root
    Example: "A radical verb form"
  • adjective:   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
    Example: "Radical leaves"
  • adjective:   (used of opinions and actions) far beyond the norm
    Example: "Radical opinions on education"
  • adjective:   markedly new or introducing radical change
    Example: "Radical political views"