Compound radical

Compound \Com"pound\, a. [OE. compouned, p. p. of compounen. See
   {Compound}, v. t.]
   Composed of two or more elements, ingredients, parts;
   produced by the union of several ingredients, parts, or
   things; composite; as, a compound word.
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         Compound substances are made up of two or more simple
         substances.                              --I. Watts.
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   {Compound addition}, {subtraction}, {multiplication},
   {division} (Arith.), the addition, subtraction, etc., of
      compound numbers.

   {Compound crystal} (Crystallog.), a twin crystal, or one
      seeming to be made up of two or more crystals combined
      according to regular laws of composition.

   {Compound engine} (Mech.), a form of steam engine in which
      the steam that has been used in a high-pressure cylinder
      is made to do further service in a larger low-pressure
      cylinder, sometimes in several larger cylinders,
      successively.

   {Compound ether}. (Chem.) See under {Ether}.

   {Compound flower} (Bot.), a flower head resembling a single
      flower, but really composed of several florets inclosed in
      a common calyxlike involucre, as the sunflower or
      dandelion.

   {Compound fraction}. (Math.) See {Fraction}.

   {Compound fracture}. See {Fracture}.

   {Compound householder}, a householder who compounds or
      arranges with his landlord that his rates shall be
      included in his rents. [Eng.]

   {Compound interest}. See {Interest}.

   {Compound larceny}. (Law) See {Larceny}.

   {Compound leaf} (Bot.), a leaf having two or more separate
      blades or leaflets on a common leafstalk.

   {Compound microscope}. See {Microscope}.

   {Compound motion}. See {Motion}.

   {Compound number} (Math.), one constructed according to a
      varying scale of denomination; as, 3 cwt., 1 qr., 5 lb.;
      -- called also {denominate number}.

   {Compound pier} (Arch.), a clustered column.

   {Compound quantity} (Alg.), a quantity composed of two or
      more simple quantities or terms, connected by the sign +
      (plus) or - (minus). Thus, a + b - c, and bb - b, are
      compound quantities.

   {Compound radical}. (Chem.) See {Radical}.

   {Compound ratio} (Math.), the product of two or more ratios;
      thus ab:cd is a ratio compounded of the simple ratios a:c
      and b:d.

   {Compound rest} (Mech.), the tool carriage of an engine
      lathe.

   {Compound screw} (Mech.), a screw having on the same axis two
      or more screws with different pitch (a differential
      screw), or running in different directions (a right and
      left screw).

   {Compound time} (Mus.), that in which two or more simple
      measures are combined in one; as, 6-8 time is the joining
      of two measures of 3-8 time.

   {Compound word}, a word composed of two or more words;
      specifically, two or more words joined together by a
      hyphen.
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Radical \Rad"i*cal\ (r[a^]d"[i^]*kal), n.
   1. (Philol.)
      (a) A primitive word; a radix, root, or simple, underived,
          uncompounded word; an etymon.
      (b) A primitive letter; a letter that belongs to the
          radix.
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                The words we at present make use of, and
                understand only by common agreement, assume a
                new air and life in the understanding, when you
                trace them to their radicals, where you find
                every word strongly stamped with nature; full of
                energy, meaning, character, painting, and
                poetry.                           --Cleland.
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   2. (Politics) One who advocates radical changes in government
      or social institutions, especially such changes as are
      intended to level class inequalities; -- opposed to
      conservative.
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            In politics they [the Independents] were, to use the
            phrase of their own time, "Root-and-Branch men," or,
            to use the kindred phrase of our own, Radicals.
                                                  --Macaulay.
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   3. (Chem.)
      (a) A characteristic, essential, and fundamental
          constituent of any compound; hence, sometimes, an
          atom.
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                As a general rule, the metallic atoms are basic
                radicals, while the nonmetallic atoms are acid
                radicals.                         --J. P. Cooke.
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      (b) Specifically, a group of two or more atoms, not
          completely saturated, which are so linked that their
          union implies certain properties, and are conveniently
          regarded as playing the part of a single atom; a
          residue; -- called also a {compound radical}. Cf.
          {Residue}.
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   4. (Alg.) A radical quantity. See under {Radical}, a.
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            An indicated root of a perfect power of the degree
            indicated is not a radical but a rational quantity
            under a radical form.                 --Davies &
                                                  Peck (Math.
                                                  Dict.)
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   5. (Anat.) A radical vessel. See under {Radical}, a.
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