ra·​tio | \ ˈrā-(ˌ)shō How to pronounce ratio (audio) , -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


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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 Early in Tuesday’s session, at least 2.5 calls are changing hands for every put in each of these stocks, with that ratio as high as 7.5 for Lumber Liquidators. Luke Kawa, Bloomberg.com, "Retail Option Traders Re-Up Bets After Stock Darlings Plummet," 7 May 2020 That ratio can be changed between races to match the car's speed to each track. David Beard, Car and Driver, "Weighing in at 1400 Pounds, with 900 Horsepower, Outlaws Drift Like Champs," 3 May 2020 That once impressive kill ratio dropped to an abysmal 1.5:1. Alex Hollings, Popular Mechanics, "Why the F-15 Is Such a Badass Plane," 17 Apr. 2020 In Kuwait, foreigners outnumber citizens by more than two to one; in Qatar and the United Arab Emirates, that ratio is nearly nine to one. Ben Hubbard, New York Times, "Coronavirus Fears Terrify and Impoverish Migrants in the Persian Gulf," 13 Apr. 2020 By the afternoon, that ratio was 23 of the 492 open orders. Michael Casagrande | Mcasagrande@al.com, al, "Shipt protest will last as long as needed, leader says," 7 Apr. 2020 The amount of money that top executives at big corporations make relative to other workers has been a growing conservation since the 2008 recession, when federal officials mandated that companies publicly disclose that ratio. Clare Duffy, CNN, "Why CEOs are giving up their salaries during the coronavirus crisis," 26 Mar. 2020 That ratio is typically 60-70 puts for every 100 calls, Frederick says. Anne Sraders, Fortune, "5 keys to decoding the stock market this week," 11 Mar. 2020 More and more investors and financial advisers have been setting an asset-allocation target—say, 60% in stocks, 40% in bonds—and rebalancing, or adjusting to restore that ratio, over time. WSJ, "Bond Funds Are Hotter Than Tesla," 7 Feb. 2020

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 entry 1

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Time Traveler for ratio

Time Traveler

The first known use of ratio was in 1660

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Statistics for ratio

Last Updated

14 May 2020

Cite this Entry

“Ratio.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ratio. Accessed 27 May. 2020.

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More Definitions for ratio


How to pronounce ratio (audio)

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 How to pronounce ratio (audio) , -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 How to pronounce ratio (audio) \
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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More from Merriam-Webster on ratio

Thesaurus: All synonyms and antonyms for ratio

Rhyming Dictionary: Words that rhyme with ratio

Spanish Central: Translation of ratio

Nglish: Translation of ratio for Spanish Speakers

Britannica English: Translation of ratio for Arabic Speakers

Britannica.com: Encyclopedia article about ratio

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