frac·​tion | \ˈfrak-shən \

Definition of fraction 

1a : a numerical representation (such as ³/₄, ⁵/₈, or 3.234) indicating the quotient of two numbers

b(1) : a piece broken off : fragment

(2) : a discrete unit : portion

2 : one of several portions (as of a distillate) separable by fractionation

3 : bit, little a fraction closer

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Synonyms for fraction


bit, fragment, piece, scrap

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Examples of fraction in a Sentence

a fraction of an inch if even a tiny fraction of that cookie broke off and fell into the delicate watch works, it could mess things up

Recent Examples on the Web

The reality is, a very large fraction of progress on technologies happens through deployment. David Roberts, Vox, "Climate change policy can be overwhelming. Here’s a guide to the policies that work.," 30 Nov. 2018 Windows is now a dwindling fraction of Microsoft’s business. Matt O'brien, The Seattle Times, "Apple’s stock sours, Microsoft’s soars. Say what?!," 27 Nov. 2018 As the Supersport race roared around us, Hayes pointed out how riders use their particular strengths to shave fractions of a second off their times. Mitchell Nicholson, Popular Mechanics, "The Great American Motorcycle Racing Revival," 7 Sep. 2018 The discovery by IceCube, built at a cost of almost $280 million (a fraction of the $10 billion collider), was especially sweet for Halzen, 74. Mark Johnson, Milwaukee Journal Sentinel, "Blazing a trail: UW professor's dream leads to breakthrough in identifying origin of cosmic rays," 12 July 2018 In the end, only a fraction of the upgrades proposed by the engineering consultants were done. Richard Horan, The Christian Science Monitor, "'The Poisoned City' tells the horrific story of Flint's contaminated water," 10 July 2018 But reducing levels of a problem protein made in the liver requires editing a large fraction of the organ’s cells. Jocelyn Kaiser, Science | AAAS, "Gene edited monkeys offer hope for heart disease patients," 9 July 2018 Since 2010, Trump’s Mar-a-Lago club has pursued more than 500 visas for foreign workers from Romania and other countries, while hiring only a fraction of domestic workers who applied for seasonal work, according to reporting by The New York Times. Skyler Swisher,, "Trump’s Mar-a-Lago wants to hire dozens of foreign workers," 6 July 2018 As a general rule, the sickest patients require the most expensive interventions, and a large fraction of the concentrated spending before death can be explained by how seriously ill these patients are. Orly Nadell Farber, STAT, "Are we spending too much on the dying? New research challenges this widely held view," 28 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fraction.' 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 fraction

14th century, in the meaning defined at sense 1a

History and Etymology for fraction

Middle English fraccioun "act or result of breaking, mathematical fraction," borrowed from Medieval Latin frāctiōn-, frāctiō "breaking, division into parts, mathematical fraction," going back to Late Latin, "breaking, weariness, illness," from Latin frag-, variant stem of frangere "to break, shatter" + -tiōn-, -tiō, suffix of verbal action — more at break entry 1

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Statistics for fraction

Last Updated

8 Dec 2018

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Time Traveler for fraction

The first known use of fraction was in the 14th century

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English Language Learners Definition of fraction

mathematics : a number (such as 1/2 or 3/4) which indicates that one number is being divided by another; also : a number (such as 3.323) that consists of a whole number and a decimal

: a part or amount of something


frac·​tion | \ˈfrak-shən \

Kids Definition of fraction

1 : a number (as ¹/₂, ²/₃, ¹⁷/₁₀₀) that indicates one or more equal parts of a whole or group and that may be considered as indicating also division of the number above the line by the number below the line

2 : a part of a whole : fragment I sold the car for a fraction of what I paid for it.


frac·​tion | \ˈfrak-shən \

Medical Definition of fraction 

: one of several portions (as of a distillate) separable by fractionation gamma globulin is a fraction of blood plasma

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Comments on fraction

What made you want to look up fraction? Please tell us where you read or heard it (including the quote, if possible).


to enclose within walls

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