ra·​tio | \ ˈrā-shē-ˌō How to pronounce ratio (audio) , -(ˌ)shō \
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 On average, their price-to-forward-earnings ratio is 28% below their 10-year average. Jinjoo Lee, WSJ, 22 Oct. 2021 In fact, if your limit increases but your spending levels stay the same, this can actually improve your credit score by reducing your credit utilization ratio. Amy Wagner And Steve Sprovach, The Enquirer, 14 Oct. 2021 Economists feared the country was heading toward insolvency — its ratio of debt to gross domestic product had surged from 60 to 93 percent between 2011 and 2015. Washington Post, 3 Oct. 2021 Highland Park ISD, for example, was highly rated for its graduation rate, its student-teacher ratio and its finances, as well as as its athletics: Niche ranked it the No. 2 best school in the state for athletes. Brandi Addison, Dallas News, 23 Sep. 2021 Divide your total monthly debt payments by your income for your debt-to-income ratio, suggests Khari Washington, broker and founder of 1st United Realty. Hiranmayi Srinivasan, Better Homes & Gardens, 13 Sep. 2021 Burnes shines in the peripheral categories with a 1.58 FIP (fielding independent pitching) among the best ever, and stats like his 0.3 home runs per nine innings, his K/BB ratio and his 1.8 walks per nine innings lead the league. Jr Radcliffe, Milwaukee Journal Sentinel, 8 Sep. 2021 Most mortgage lenders require your DTI ratio to be less than 43 percent when calculating all your debt against your monthly income, including your mortgage payment. Casey Bond, Robb Report, 6 Sep. 2021 Vesia is holding lefty batters to a .100 average and no home runs, and while his strikeout/walk ratio shrinks from 22-6 against lefties to 19-11 against right-handers, his overall 0.87 WHIP is sufficient to survive in this three-batter minimum era. Gabe Lacques, USA TODAY, 2 Sep. 2021

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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Dictionary Entries Near ratio

rating nut


ratio arm

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Statistics for ratio

Last Updated

26 Oct 2021

Cite this Entry

“Ratio.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ratio. Accessed 26 Oct. 2021.

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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 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

More from Merriam-Webster on 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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