ra·tio | \ˈrā-(ˌ)shō, -shē-ˌō\
plural ratios

Definition of ratio 

1a : the indicated quotient of two mathematical expressions

b : the relationship in quantity, amount, or size between two or more things : proportion

2 : the expression of the relative values of gold and silver as determined by a country's currency laws

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Synonyms for ratio


proportion, rate

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Examples of ratio in a Sentence

What is the length-to-width ratio? the ratio of students to teachers in the school is nine to one

Recent Examples on the Web

His assist-to-turnover ratio of 2.33-to-1 exceeded Jrue Holiday’s (2.28), Dennis Schröder’s (2.28), Kyrie Irving’s (2.19) and Goran Dragic’s (2.16). Josh Robbins, OrlandoSentinel.com, "Magic Mailbag: What’s the deal with Orlando’s point guard situation?," 12 July 2018 Their defensive efficiency ratio — a measure of a team’s ability to turn balls in play into outs — is by far the worst in baseball. Noah Trister, The Seattle Times, "Dreadful Orioles bringing back memories of ’88," 9 July 2018 From the rotation, Stripling has 86 strikeouts and 7 walks, meaning that his ratio is more than double his closest competition as a starter. Emma Baccellieri, SI.com, "All-Star Game Snubs: Blake Snell, Max Muncy and Seven Other Roster Whiffs," 8 July 2018 Its payout ratio in 2017 was 99 percent, according to Barclays. Peter Eavis, New York Times, "Banks Are Paying Out Billions to Shareholders. We Put the Numbers in Context.," 29 June 2018 Higher debt levels: In 2017, Fannie Mae also raised its maximum debt-to-income ratio, which compares monthly gross income with the minimum payment on all recurring debt, from 45 to 50 percent. Michele Lerner, chicagotribune.com, "It's easier to get a mortgage in 2018, according to a new study," 20 June 2018 Its bad-loan ratio is one of the highest among its peers. Anto Antony, Bloomberg.com, "ICICI Bank CEO Kochhar to Go on Leave as Allegations Probed," 19 June 2018 His walks are the fewest among rookie starters in the majors with as many starts and his 5.22 strikeout-to-walk ratio is the best among rookie starters with at least 45 innings pitched. Andre C. Fernandez, miamiherald, "Former Canes pitcher is back home to face the Marlins as regular major-league starter," 13 June 2018 And though centenarians are spread across the country, in Okinawa, their ratios are among the world's highest: about 50 per 100,000 people. Emiko Jozuka, CNN, "In the 'land of the immortals': Japan's centenarian pop band," 8 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ratio.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of ratio

1660, in the meaning defined at sense 1a

History and Etymology for ratio

Latin, computation, reason — more at reason

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Statistics for ratio

Last Updated

16 Oct 2018

Look-up Popularity

Time Traveler for ratio

The first known use of ratio was in 1660

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More Definitions for ratio



English Language Learners Definition of ratio

: the relationship that exists between the size, number, or amount of two things and that is often represented by two numbers


ra·tio | \ˈrā-shō, -shē-ˌō\
plural ratios

Kids Definition of ratio

: the relationship in number or quantity between two or more things the ratio of teachers to students


ra·tio | \ˈrā-(ˌ)shō, -shē-ˌō \
plural ratios

Medical Definition of ratio 

: the relationship in quantity, amount, or size between two or more things — see sex ratio

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Comments on ratio

What made you want to look up ratio? Please tell us where you read or heard it (including the quote, if possible).


one that holds something together

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