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noun arith·me·tic \ə-ˈrith-mə-ˌtik\

Simple Definition of arithmetic

  • : a branch of mathematics that deals with numbers and their addition, subtraction, multiplication, and division

  • : the act or process of calculating a number

Source: Merriam-Webster's Learner's Dictionary

Full Definition of arithmetic

  1. 1 a :  a branch of mathematics that deals usually with the nonnegative real numbers including sometimes the transfinite cardinals and with the application of the operations of addition, subtraction, multiplication, and division to them b :  a treatise on arithmetic

  2. 2 :  computation, calculation


play \ˌer-ith-ˈme-tik, ˌa-rith\ or


play \-ti-kəl\ adjective


play \-ti-k(ə-)lē\ adverb


play \ə-ˌrith-mə-ˈti-shən\ noun

Examples of arithmetic in a sentence

  1. a software program that will do the arithmetic for you

  2. <I haven't actually done the arithmetic yet, but I suspect we're losing money on the deal.>

Origin and Etymology of arithmetic

Middle English arsmetrik, from Anglo-French arismatike, from Latin arithmetica, from Greek arithmētikē, from feminine of arithmētikos arithmetical, from arithmein to count, from arithmos number; akin to Old English rīm number, and perhaps to Greek arariskein to fit

First Known Use: 15th century

Other Mathematics and Statistics Terms

ARITHMETIC Defined for Kids


noun arith·me·tic \ə-ˈrith-mə-ˌtik\

Definition of arithmetic for Students

  1. 1 :  a science that deals with the addition, subtraction, multiplication, and division of numbers

  2. 2 :  an act or method of adding, subtracting, multiplying, or dividing


\ˌer-ith-ˈme-tik\ or


\-ti-kəl\ adjective

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