Meaning of ARITHMETIC in English
[noun] [U] - the process of making calculations such as adding, multiplying, etc. using numbersI'm not very good at arithmetic.We've got an arithmetic test at school tomorrow.The teacher always has to correct Nick's arithmetic.I can't work out which of these packets of washing powder is cheaper - could you do the arithmetic for me?Mental arithmetic is calculations done in the mind.He did some quick mental arithmetic and then checked his answer on the calculator.
Cambridge English vocab. Кембриджский английский словарь. 2012