ratio

noun
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

Synonyms

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

The trend for self-perfection has birthed apps (FaceTune), portable lighting (Lumee Cases), and a trend in plastic surgery to realign noses and eyebrows and eyeballs to a more pleasing digital ratio. Steff Yotka, Vogue, "“Fashion For Bank Robbers” Is an Insta-Obsession for the Anti-Selfie Set," 17 Apr. 2019 Start with a one to 10 ratio of ginger oil to vaseline, Dr. Madan advises — that's about seven or so drops of oil per teaspoon of petroleum jelly. Caroline Picard, Good Housekeeping, "How to Use Ginger Oil for Swelling and Inflammation, According to a Dermatologist," 15 Jan. 2019 The Amp’s signal to noise ratio is 116dB with under 0.1 percent total harmonic distortion. Chris Welch, The Verge, "The new Sonos Amp is coming to save your old speakers," 29 Aug. 2018 Pashayan and her colleagues determined that to maximize the benefit-to-harm ratio, the 30 percent of women at the lowest risk do not need mammograms. Orly Nadell Farber, STAT, "New approach to breast cancer screening — tailoring guidelines for each patient — may save lives and money, study says," 5 July 2018 Do as many chefs do and go for an 80/20 lean to fat ratio of high quality meat. Natalie B. Compton, GQ, "How to Cook a Hamburger Like a Chef," 26 June 2018 Takes care of the ball (2.1 assist to turnover ratio). Jeremy Woo, SI.com, "2018 NBA Draft: Tony Carr Scouting Report and Highlights," 17 June 2018 Both feature a high level of clinical support and academic individualization, and high staff to student ratio. Erika Butler, The Aegis, "Arrow in Harford closing Creswell school, expanding in Riverside," 18 May 2018 Called Chatterbaby, the free app analyzes changes in frequency and patterns in the sound to silence ratio to tell parents why their kiddo is crying. Megan Molteni, WIRED, "Can This AI-Powered Baby Translator Help Diagnose Autism?," 11 May 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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Learn More about ratio

Statistics for ratio

Last Updated

15 May 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

ratio

noun

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

ratio

noun
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

ratio

noun
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

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