ratio

noun

ra·​tio ˈrā-shē-ˌō How to pronounce ratio (audio)
-(ˌ)shō
plural ratios
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

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
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.
Keeping on the right side of the say/do ratio will help ensure your team ends up with more victories than defeats. Amy Cappellanti-Wolf, Forbes.com, 22 May 2025 That ratio probably will change this year, considering Floyd, Walker, Pearce Jr. and fellow edge rushers Arnold Ebiketie and Bralen Trice seem like locks to make the roster. Josh Kendall, New York Times, 22 May 2025 The price-to-earnings ratio for the S&P 500, based on earnings estimates for the next 12 months, was at 21.7 as of Monday, well above its long-term average of 15.8, according to LSEG Datastream. Davide Barbuscia, USA Today, 22 May 2025 Berkeley has the lowest rent-to-price ratio of the 300 cities, meaning its more cost-effective to rent there, than to buy a home. Anne Marie D. Lee, CBS News, 21 May 2025 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

Browse Nearby Words

Cite this Entry

“Ratio.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ratio. Accessed 29 May. 2025.

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
plural ratios
: the relationship in quantity, amount, or size between two or more things see sex ratio

More from Merriam-Webster on ratio

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