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noun frac·tion \ˈfrak-shən\

Simple 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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of fraction

  1. 1 a :  a numerical representation (as 34, 58, or 3.234) indicating the quotient of two numbers b (1) :  a piece broken off :  fragment (2) :  a discrete unit :  portion

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

  3. 3 :  bit, little <a fraction closer>

Examples of fraction in a sentence

  1. a fraction of an inch

  2. <if even a tiny fraction of that cookie broke off and fell into the delicate watch works, it could mess things up>

Origin and Etymology of fraction

Middle English fraccioun, from Late Latin fraction-, fractio act of breaking, from Latin frangere to break — more at break

First Known Use: 14th century

Other Mathematics and Statistics Terms

Rhymes with fraction

FRACTION Defined for Kids


noun frac·tion \ˈfrak-shən\

Definition of fraction for Students

  1. 1 :  a number (as 12, 23, {frac17/100}) 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. 2 :  a part of a whole :  fragment <I sold the car for a fraction of what I paid for it.>

Word Root of fraction

The Latin word frangere, meaning “to break,” and its form fractus give us the roots frag and fract. Words from the Latin frangere have something to do with breaking. Something fragile is easily broken. A fraction is a portion broken off from a whole. To fracture something, such as a bone, is to break it. A fragment is a part that has been broken off from something larger or that is incomplete.

Medical Dictionary


noun frac·tion \ˈfrak-shən\

Medical Definition of fraction

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

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