Definition of fraction in US English:



  • 1A numerical quantity that is not a whole number (e.g. 1/2, 0.5).

    • ‘Use the method above to convert it into a fraction with whole numbers in the denominator.’
    • ‘You may have to multiply both fractions by different numbers to produce the same denominator for both fractions.’
    • ‘Column addition was performed on whole numbers and then on fractions.’
    • ‘The aim of the first part is to introduce the Hindu numerals, to explain a place value system and to describe addition, multiplication and other arithmetic operations on integers and fractions in both decimal and sexagesimal notation.’
    • ‘Although all these fractions are written differently, they all represent the same quantity.’
    • ‘It looks first at area problems, then looks at rules for the addition, subtraction, multiplication and division of fractions.’
    • ‘The math course consists of five subject areas: understanding numbers, using whole numbers, using decimals, using fractions and per cents, and working with data.’
    • ‘The Mathematics Computation subtest assesses skills in computing with whole numbers, fractions, mixed numbers, decimals, and algebraic equations.’
    • ‘Basic operations with whole numbers, fractions, and decimals were required to solve some problems, although many items required no calculations.’
    • ‘To convert a fraction to a percentage, divide the numerator by the denominator.’
    • ‘They should also be able to understand basic maths and geometry, including fractions, decimals, multiplication and division.’
    • ‘Specifically, children's responses to the less familiar quantities of zero and fractions could shed light on their performance with the more familiar whole numbers.’
    • ‘These most rarely occurring topics were: angles in a quadrilateral, fractions, fraction multiplication, properties of triangles, and the Pythagorean theorem.’
    • ‘Sometimes when working with fractions, the hardest thing to find is a common denominator.’
    • ‘What are the rules for converting fractions to binary and octal and vice versa?’
    • ‘Others would rewrite the fractions using common denominators.’
    • ‘Possibly as a consequence of that, the Greek mathematicians thought of fractions in terms of ratios of integers, rather than numbers.’
    • ‘Students added several combinations of wood in whole numbers and mixed fractions as they tested the most economical ways to use the lumber.’
    • ‘In other words, a number is rational if we can write it as a fraction where the numerator and denominator are both integers.’
    • ‘The line between the numerator and denominator is known as the fraction bar.’
  • 2A small or tiny part, amount, or proportion of something.

    ‘he hesitated for a fraction of a second’
    ‘her eyes widened a fraction’
    • ‘Fortunately, a salvage unit was available, at a fraction of that amount.’
    • ‘Only a fraction of the huge amount of money we pay in road taxes is put into the maintenance and building of roads.’
    • ‘The parasitic wasp is quite tiny, only a fraction of the size of an adult fly.’
    • ‘Turns out that he produces some rather wonderful music consisting almost entirely of samples, usually only a fraction of a second long.’
    • ‘In this way hundreds of small adjustments can be made in a fraction of the time needed by more traditional methods.’
    • ‘In terms of proportion, only a fraction of local cotton is transformed and exported as finished goods.’
    • ‘However, the true cost is a fraction of this amount.’
    • ‘Her eyes rest on me for a second, and I swear I can see a tiny ghost of a smile for a fraction of a second.’
    • ‘They had acquired the land for a tiny fraction of that amount.’
    • ‘The new process allowed mass production using a fraction of the amount of silver thereby reducing costs.’
    • ‘If they did, the insurance company would have been charged a fraction of that amount.’
    • ‘That amount was only a fraction of the true value of the business, according to farmers of the former co-op.’
    • ‘No one would ever notice a fraction of a cent but with the amount of financial transactions going on those fractions mounted up.’
    • ‘Joule also invented extremely precise thermometers, which could measure temperature changes to within fractions of a degree Fahrenheit.’
    • ‘It's only a fraction of the amount of money necessary to attend most private schools.’
    • ‘The council currently spends a fraction of this amount on all its other roads combined.’
    • ‘Each of those putative atoms of element 115 disintegrated within fractions of a second by spontaneously ejecting an alpha particle, which contains two protons and two neutrons.’
    • ‘Her goal was $60,000 but she was only able to get a fraction of that amount.’
    • ‘He said hundreds of lives could be saved on the roads every year for a fraction of the amount being spent on rail safety.’
    • ‘The victim would be left with only £5,000-a fraction of the amount intended to cover his pain and suffering.’
    tiny part, small part, fragment, snippet, snatch, smattering, selection
    tiny amount, little, bit, touch, hint, soupçon, trifle, mite, scrap, dash, spot, modicum, shade, jot
    View synonyms
    1. 2.1 A dissenting group within a larger one.
      • ‘Revisionists distinguished between fractions of the ruling class in a significant way.’
      • ‘Most relevant to this essay is Bourdieu's idea of social class fractions that depend on the composition of their three capitals, cultural, social, and economic.’
      • ‘The lower middle class experiences deprivation relative to the new middle class fractions above them in terms of wealth, power, and prestige.’
      • ‘Today's Muslim is put under the spotlight and has been critically scrutinized not only by the non-Muslim communities' worldwide but also from fractions within our own community.’
      • ‘For those unversed in the fractions and factions of Labour local politics, here is a glossary.’
      • ‘The Greens have their pro and anti-capitalist fractions and are working though the issue.’
      • ‘On the other hand, we can see very clearly the fractions within the hardliner camp, again in contrast to what the pro-participation group is saying.’
      • ‘Fundamentalism attracts different class fractions across cultural locales in a common struggle against a diminishing or diminished social status, influence, and power.’
      • ‘Class fractions are a fundamental feature of corporate capitalism and can become particularly potent fault lines.’
      • ‘The following year a follow up album was released, Time and a Word, by which time fractions were beginning to open up within the ranks of the band as the battle for leadership started.’
      • ‘These shifts did not occur without inner turmoil and conflict, and many fractions continue to struggle within the party today.’
      • ‘The state, then, is the condensation of a hegemonic relationship between dominant classes and class fractions.’
      • ‘I think they are likely to lead to conflicts between fragments and fractions within ruling corporate elites.’
      • ‘It is more than simply a political alliance between social forces represented by classes or fractions of classes.’
  • 3Chemistry
    Each of the portions into which a mixture may be separated by a process in which the individual components behave differently according to their physical properties.

    • ‘The cell lysate was then centrifuged at 27 000 g for 30 min at 4°C and the soluble and insoluble fractions were separated through a syringe.’
    • ‘The gum arabic fractions were collected separately and extracted with water/chloroform.’
    • ‘Cells were collected 48 hr later, and nuclear and cytoplastic fractions were separated.’
    • ‘The aqueous, ethanol and ethyl acetate fractions were slowly evaporated to dryness under vacuum and stored at 4 degreesC for biological study.’
    • ‘Soluble and insoluble fractions were separated by centrifugation at 8 000 g for 30 min at the extraction temperature.’
    • ‘The ethyl acetate of the combined organic fractions was evaporated under reduced pressure.’
    • ‘After incubation, the samples were treated as above, and the supernatant fractions were lyophilized.’
    • ‘Oil refining separates the various fractions of petroleum by a process called fractional distillation and takes place in a large plant called a refinery.’
    • ‘Benzene is manufactured industrially by dehydrogenation and dealkylation of appropriate fractions of petroleum.’
    • ‘Total lipid extracts were separated into neutral and polar lipid fractions by column chromatography on Florisil 60-100 mesh.’
    • ‘This is a generic term for the light hydrocarbon fractions found associated with most oil deposits.’
    • ‘The acetone and methanol fractions were combined and dried under nitrogen.’
    • ‘The majority of the manufacturing is from the catalytic cracking of ethane, petroleum fractions, and crude oil.’
    • ‘Both are produced by refining crude oil, but the kerosene fraction of the oil is a little heavier.’
    • ‘The supernatant and the precipitate fractions were separated.’
    • ‘The resulting soluble organic fractions were analysed for polynuclear aromatic compounds and tested for mutagenic effects.’
    • ‘Of course, there is some overlap of the boiling points and molecular size for these fractions.’
  • 4usually the Fraction(in the Christian Church) the breaking of the Eucharistic bread.


Late Middle English: via Old French from ecclesiastical Latin fractio(n-) ‘breaking (bread)’, from Latin frangere ‘to break’.