The Collaborative International Dictionary of English v.0.48:

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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The Collaborative International Dictionary of English v.0.48:

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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