The mathematics of integers, rational numbers, real numbers, or complex numbers under addition, subtraction, multiplication, and division.
adj. ar·ith·met·ic (ăr′ĭth-mĕtĭk) also ar′ith·meti·cal (ăr′ĭth-mĕtĭ-kəl)
1. Of or relating to arithmetic.
2. Changing according to an arithmetic progression: The increase in the food supply is arithmetic.
[Middle English arsmetike, from Old French arismetique, from Medieval Latin arismetica, alteration of Latin arithmētica, from Greek arithmētikē (tekhnē), (art) of counting, feminine of arithmētikos, from arithmein, to count, from arithmos, number; see ar- in the Appendix of Indo-European roots.]
a·rith′me·tician (-tĭshən) n.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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