\Pro*por"tion\, n. [F., fr. L. proportio; pro before
+ portio part or share. See {Portion}.]
1. The relation or adaptation of one portion to another, or
   to the whole, as respect magnitude, quantity, or degree;
   comparative relation; ratio; as, the proportion of the
   parts of a building, or of the body.
         The image of Christ, made after his own proportion.
                                               --Ridley.
         Formed in the best proportions of her sex. --Sir W.
                                               Scott.
         Documents are authentic and facts are true precisely
         in proportion to the support which they afford to
         his theory.                           --Macaulay.
2. Harmonic relation between parts, or between different
   things of the same kind; symmetrical arrangement or
   adjustment; symmetry; as, to be out of proportion. ``Let
   us prophesy according to the proportion of faith.'' --Rom.
   xii. 6.
3. The portion one receives when a whole is distributed by a
   rule or principle; equal or proper share; lot.
         Let the women . . . do the same things in their
         proportions and capacities.           --Jer. Taylor.
4. A part considered comparatively; a share.
5. (Math.)
   (a) The equality or similarity of ratios, especially of
       geometrical ratios; or a relation among quantities
       such that the quotient of the first divided by the
       second is equal to that of the third divided by the
       fourth; -- called also {geometrical proportion}, in
       distinction from arithmetical proportion, or that in
       which the difference of the first and second is equal
       to the difference of the third and fourth.
Note: Proportion in the mathematical sense differs from
      ratio. Ratio is the relation of two quantities of the
      same kind, as the ratio of 5 to 10, or the ratio of 8
      to 16. Proportion is the sameness or likeness of two
      such relations. Thus, 5 to 10 as 8 to 16; that is, 5
      bears the same relation to 10 as 8 does to 16. Hence,
      such numbers are said to be in proportion. Proportion
      is expressed by symbols thus: a:b::c:d, or a:b = c:d,
      or a/b = c/d.
   (b) The rule of three, in arithmetic, in which the three
       given terms, together with the one sought, are
       proportional.
{Continued proportion}, {Inverse proportion}, etc. See under
   {Continued}, {Inverse}, etc.
{Harmonical, or Musical}, {proportion}, a relation of three
   or four quantities, such that the first is to the last as
   the difference between the first two is to the difference
   between the last two; thus, 2, 3, 6, are in harmonical
   proportion; for 2 is to 6 as 1 to 3. Thus, 24, 16, 12, 9,
   are harmonical, for 24:9::8:3.
{In proportion}, according as; to the degree that. ``In
   proportion as they are metaphysically true, they are
   morally and politically false.'' --Burke.

\Pro*por"tion\, v. t. [imp. & p. p. {Proportioned};
p. pr. & vb. n. {Proportioning}.] [Cf. F. proportionner. Cf.
{Proportionate}, v.]
1. To adjust in a suitable proportion, as one thing or one
   part to another; as, to proportion the size of a building
   to its height; to proportion our expenditures to our
   income.
         In the loss of an object we do not proportion our
         grief to the real value . . . but to the value our
         fancies set upon it.                  --Addison.
2. To form with symmetry or suitableness, as the parts of the
   body.
         Nature had proportioned her without any fault. --Sir
                                               P. Sidney.
3. To divide into equal or just shares; to apportion.