<p><strong>noun</strong></p><ul><li>the method or process of computation with figures: the most elementary branch of mathematics.</li><li>Also called higher arithmetic.</li><li>the theory of numbers; the study of the divisibility of whole numbers, the remainders after division, etc.</li><li>a book on this subject.</li></ul><p><strong>adjective</strong></p><ul><li>Also arithmetical.</li><li>of or relating to arithmetic.</li></ul>