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


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

Free writing begins at 7 p.m.; dancing commences at 9 p.m. (Please take note of this welcome writing-to-dancing ratio. Agatha French, latimes.com, "Looking for literary fun? These 5 L.A. book events include magic and a little library on wheels," 5 July 2019 The coach-to-player ratio in college baseball is the worst of any of the major intercollegiate sport; as is the number of scholarships. Mike Bianchi, orlandosentinel.com, "College baseball should be ashamed of ‘dehumanizing’ way it treats unpaid assistants, debt-ridden players | Commentary," 29 June 2019 New data reveal that China’s total debt-to-GDP ratio, excluding the financial sector, leapt by more than five percentage points in the first quarter of 2019, to nearly 250% of GDP. The Economist, "Overmatched policymakers risk toppling the world economy into trouble," 25 June 2019 Perhaps the 2:1 male ratio in the North Pacific has led to our males singing to attract females. Amy Woodyatt, CNN, "Song of rare whale 'crying for mate' recorded for the first time," 20 June 2019 Perhaps the 2:1 male ratio in the North Pacific has led to our males singing to attract females. Fox News, "Rare whale near Alaska recorded singing for first time," 20 June 2019 In Lebanon, for example, there are 156 refugees per 1,000 inhabitants, the highest such ratio in 2018. Ana Campoy, Quartz, "Rich countries only took in 16% of the world’s refugees in 2018," 19 June 2019 Whitman said due to the proportionality of the male-female student ratio on campus the university would be in compliance with Title IX without adding a women’s program. Shannon Ryan, chicagotribune.com, "Illini will take a ‘hiatus’ from their annual basketball game at the United Center," 18 June 2019 Things were rosy when March rolled around and Ole had been in the job for a few months, with the Norwegian having the second best win ratio in United history by that point. SI.com, "7 Players Who Returned to Their Former Club as Manager & How They Fared," 17 June 2019

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

10 Jul 2019

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 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

Rhyming Dictionary: Words that rhyme with ratio

Thesaurus: All synonyms and antonyms for 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

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).


food or victuals

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