noun arith·me·tic \ə-ˈrith-mə-ˌtik\

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

: the act or process of calculating a number

Full Definition of ARITHMETIC

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
ar·ith·met·ic \ˌer-ith-ˈme-tik, ˌa-rith\ or ar·ith·met·i·cal \-ti-kəl\ adjective
ar·ith·met·i·cal·ly \-ti-k(ə-)lē\ adverb
arith·me·ti·cian \ə-ˌrith-mə-ˈti-shən\ noun

Examples of ARITHMETIC

  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.>


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

abscissa, denominator, divisor, equilateral, exponent, hypotenuse, logarithm, oblique, radii, rhomb
ARITHMETIC Defined for Kids


noun arith·me·tic \ə-ˈrith-mə-ˌtik\

Definition of ARITHMETIC for Kids

:  a science that deals with the addition, subtraction, multiplication, and division of numbers
:  an act or method of adding, subtracting, multiplying, or dividing
arith·met·ic \ˌer-ith-ˈme-tik\ or ar·ith·met·i·cal \-ti-kəl\ adjective
How to use a word that (literally) drives some people nuts.
Test your vocab with our fun, fast game
Ailurophobia, and 9 other unusual fears