proportion

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pro·por·tion / prəˈpôrshən/ • n. a part, share, or number considered in comparative relation to a whole: the proportion of greenhouse gases in the atmosphere is rising. ∎  the relationship of one thing to another in terms of quantity, size, or number; the ratio: the proportion of exams to schoolwork the bleach can be diluted with water in the proportion one part bleach to ten parts water. ∎  (proportions) the comparative measurements or size of different parts of a whole: the view of what constitutes perfect bodily proportions changes from one generation to the next. ∎  (proportions) dimensions; size: the room, despite its ample proportions, seemed too small for him. ∎  the correct, attractive, or ideal relationship in size or shape between one thing and another or between the parts of a whole: perceptions of color, form, harmony, and proportion. • v. [tr.] formal adjust or regulate (something) so that it has a particular or suitable relationship to something else: a life after death in which happiness can be proportioned to virtue. PHRASES: in proportion according to a particular relationship in size, amount, or degree: each region was represented in proportion to its population. ∎  in comparison with; in relation to: the cuckoo's eggs are unusually small in proportion to its size. ∎  in the correct or appropriate relation to the size, shape, or position of other things: her figure was completely in proportion. ∎  correctly or realistically regarded in terms of relative importance or seriousness: the problem has to be kept in proportion. out of proportion in the wrong relation to the size, shape, or position of other things: the sculpture seemed out of proportion to its surroundings. ∎  greater or more serious than is necessary or appropriate: the award was out of all proportion to the alleged libel. ∎  wrongly or unrealistically regarded in terms of relative importance or seriousness. sense of proportion the ability to judge the relative importance or seriousness of things.DERIVATIVES: pro·por·tion·less adj.

proportion in mathematics, the equality of two ratios . Two pairs of quantities a,b and c,d are in proportion if their ratios a / b and c / d are equal, i.e., if the equation a / b = c / d is true. For example, the lengths of two sides of any triangle and the lengths of the corresponding two sides of any similar (same-shaped) triangle are in proportion, for the ratio of the two sides of the first can be proved to be the same as the ratio of the two sides of the second. The proportion a / b = c / d was formerly written a : b :: c : d and is read as "a is to b as c is to d." In this form it is customary to call b and c the means and a and d the extremes. These terms are used in the statement of the rule—the product of the means equals the product of the extremes. When the proportion is written in equation form, however, this rule is seen to be simply the result of a familiar algebraic operation. Similarly all the other rules stated for proportions become obvious when the proportion is written as an equation and the usual rules of algebra are applied. The special proportion a / b = b /( a + b ) is known as the Divine Proportion, or Golden Section .

proportion comparative part, share; comparative relation, relative size. XIV (not fully current before XVI). — (O)F. proportion or L. prōportiō, -ōn-, derived from phr. prō portiōne proportionally, i.e. prō PRO-1 + abl. of portiō PORTION.
So vb. make proportionate. XIV. — (O)F. or medL. prōportiōnāre. proportionable XIV. — Late L. proportional XIV (sb.). — L. proportionate XIV. — Late L.

proportion. In architecture, a system of relationships of parts to each other and to the whole, often governed by a standard unit of length called a module based e.g. on half the diameter of a Classical column.

Bibliography

Kruft (1994);
Scholfield (1958);
Wittkower (1998)

proportion Mathematical relation of equality between two ratios, having the form a/b = c/d. A continued proportion is a group of three or more quantities, each bearing the same ratio to its successor, as in 1:3:9:27:81.

proportion. Conception in medieval mus. theory of relationship between vibration nos. of notes and also between their time-signatures in mensural notation expressed by fractions.

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