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noun pro·por·tion \prə-ˈpȯr-shən\

Simple Definition of proportion

  • : an amount that is a part of a whole

  • : the relationship that exists between the size, number, or amount of two things

  • : the correct or appropriate relationship between the size, shape, and position of the different parts of something

Source: Merriam-Webster's Learner's Dictionary

Full Definition of proportion

  1. 1 :  harmonious relation of parts to each other or to the whole :  balance, symmetry

  2. 2 a :  proper or equal share <each did her proportion of the work> b :  quota, percentage

  3. 3 :  the relation of one part to another or to the whole with respect to magnitude, quantity, or degree :  ratio

  4. 4 :  size, dimension

  5. 5 :  a statement of equality between two ratios in which the first of the four terms divided by the second equals the third divided by the fourth (as in 4/2=10/5) — compare extreme 1b, mean 1c

in proportion

Examples of proportion in a sentence

  1. His ears were drawn out of proportion with his head.

  2. The size of the window seems out of proportion with the height of the wall.

Origin of proportion

Middle English proporcion, from Anglo-French, from Latin proportion-, proportio, from pro for + portion-, portio portion — more at for

First Known Use: 14th century

Other Mathematics and Statistics Terms

Rhymes with proportion



verb, pro·por·tion

Definition of proportion

proportionedproportioning play \-sh(ə-)niŋ\

  1. transitive verb
  2. 1 :  to adjust (a part or thing) in size relative to other parts or things

  3. 2 :  to make the parts of harmonious or symmetrical

  4. 3 :  apportion, allot

14th Century

First Known Use of proportion

14th century

PROPORTION Defined for Kids


noun pro·por·tion \prə-ˈpȯr-shən\

Definition of proportion for Students

  1. 1 :  the size, number, or amount of one thing or group of things as compared to that of another thing or group of things <The proportion of boys to girls in our class is two to one.>

  2. 2 :  a balanced or pleasing arrangement <The oversize garage is out of proportion with the house.>

  3. 3 :  a statement of the equality of two ratios (as {frac4/2} = {frac10/5})

  4. 4 :  a fair or just share <I did my proportion of the work.>

  5. 5 :  size, shape, or extent of something <It was a crisis of large proportions.>

Seen and Heard

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to manage or play awkwardly

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