proportional
Americanadjective
-
having due proportion; corresponding.
- Synonyms:
- proportionate, consonant, accordant, harmonious
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being in or characterized by proportion.
-
of, relating to, or based on proportion; relative.
-
Mathematics.
-
(of two quantities) having the same or a constant ratio or relation.
The quantities y and x are proportional if y/x = k, where k is the constant of proportionality.
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(of a first quantity with respect to a second quantity) a constant multiple of.
The quantity y is proportional to x if y = kx, where k is the constant of proportionality.
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adjective
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of, involving, or being in proportion
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maths having or related by a constant ratio
noun
Other Word Forms
Etymology
Origin of proportional
First recorded in 1350–1400; Middle English proporcional, from Latin prōportiōnālis; see proportion, -al 1
Explanation
The adjective proportional describes something that has a relative size or amount to something else. When you're a mom, you know it's best to make sure chores are given out proportional amounts according to age and size of your kids. The United States has proportional representation in Congress, meaning that Congressional districts are divided according to the population, set after each census. The adjective proportional can also be used to describe something that has a constant ratio. This usage is especially common in math to describe things like proportional triangles or proportional variables. Proportionate is often interchangeable with proportional.
Vocabulary lists containing proportional
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Dear Martin
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Steve Jobs's Commencement Address (2005)
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
The researchers concluded that prenatal exposure to CPF appears to cause persistent disturbances in brain development that are proportional to the amount of exposure a child received before birth.
From Science Daily • May 21, 2026
In 2022, Labour members at the party's annual conference voted in favour of a commitment to introduce proportional representation for general elections.
From BBC • May 19, 2026
Yet the party performed far better on regional lists - where parties that do not fare as well in constituencies can make gains thanks to a more proportional voting system.
From BBC • May 8, 2026
Her face looked slimmer, younger and more proportional.
From The Wall Street Journal • May 7, 2026
He looks like the Vitruvian Man, whom he would later draw—the perfectly proportional human whose outstretched limbs all touch the sides of a circle.
From "The Mona Lisa Vanishes" by Nicholas Day
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.