compound interest

from 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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from The Collaborative International Dictionary of English v.0.48

Interest \In"ter*est\, n. [OF. interest, F. int['e]r[^e]t, fr.
   L. interest it interests, is of interest, fr. interesse to be
   between, to be difference, to be importance; inter between +
   esse to be; cf. LL. interesse usury. See {Essence}.]
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   1. Excitement of feeling, whether pleasant or painful,
      accompanying special attention to some object; concern; a
      desire to learn more about a topic or engage often in an
      activity.
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   Note: Interest expresses mental excitement of various kinds
         and degrees. It may be intellectual, or sympathetic and
         emotional, or merely personal; as, an interest in
         philosophical research; an interest in human suffering;
         the interest which an avaricious man takes in money
         getting.
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               So much interest have I in thy sorrow. --Shak.
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   2. (Finance, Commerce) Participation in advantage, profit,
      and responsibility; share; portion; part; as, an interest
      in a brewery; he has parted with his interest in the
      stocks.
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   3. Advantage, personal or general; good, regarded as a
      selfish benefit; profit; benefit.
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            Divisions hinder the common interest and public
            good.                                 --Sir W.
                                                  Temple.
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            When interest calls of all her sneaking train.
                                                  --Pope.
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   4. (Finance) A fee paid for the use of money; a fee paid for
      a loan; -- usually reckoned as a percentage; as, interest
      at five per cent per annum on ten thousand dollars.
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            They have told their money, and let out
            Their coin upon large interest.       --Shak.
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   5. Any excess of advantage over and above an exact equivalent
      for what is given or rendered.
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            You shall have your desires with interest. --Shak.
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   6. The persons interested in any particular business or
      measure, taken collectively; as, the iron interest; the
      cotton interest.
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   {Compound interest}, interest, not only on the original
      principal, but also on unpaid interest from the time it
      fell due.

   {Simple interest}, interest on the principal sum without
      interest on overdue interest.
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