ratio

noun

ra·​tio ˈrā-shē-ˌō How to pronounce ratio (audio)
-(ˌ)shō
plural ratios
Synonyms of rationext
1
a
: 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

Synonyms of 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
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Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
In its ruling, the court said the $644 million award was based on an asset division ratio under which Roh receives one-third and Chey retains two-thirds, and that its judgment was in line with the Supreme Court ruling. — Stephanie Yang, CNN Money, 24 July 2026 Cranberry, pomegranate, cherry—really any fruit juice of your choice will work using the same ratio. — Maggie Meyer Glisan, Better Homes & Gardens, 23 July 2026 There’s no magic number for when a debt-to-GDP ratio becomes dangerous, but Japan’s 204% signifies that the country’s national public debt is double the size of its economy. — Sasha Rogelberg, Fortune, 23 July 2026 For an insurer, that could mean improving the combined ratio through fewer claims delays and reduced compliance risk. — Murthy Malapaka, Forbes.com, 23 July 2026 See All Example Sentences for ratio

Word History

Etymology

Latin, computation, reason — more at reason entry 1

First Known Use

1660, in the meaning defined at sense 1a

Time Traveler
The first known use of ratio was in 1660

Phrases Containing ratio

Rhymes for ratio

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Browse Nearby Words

rating nut
ratio
ratio arm
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Cite this Entry

“Ratio.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ratio. Accessed 26 Jul. 2026.

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Kids Definition

ratio

noun
ra·​tio ˈrā-shō How to pronounce ratio (audio)
-shē-ˌō
plural ratios
1
: the quotient of two numbers or mathematical expressions
the ratio of 6 to 3 may be expressed as 6:3, ⁶⁄₃, and 2
2
: the relationship in quantity, amount, or size between two or more things
women outnumbered men in the ratio of three to one

Medical Definition

ratio

noun
ra·​tio ˈrā-(ˌ)shō, -shē-ˌō How to pronounce ratio (audio)
plural ratios
: 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.com: Encyclopedia article about ratio

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